Final Exam 2 (20%)

Question

A string p is a prefix of a string s if the leading characters of s are identical to p. For example, "abc" is a prefix of "abcde". Develop a function prefix that checks if a C string p is a prefix of another C string s.

p是s的前綴若s開頭的一段字串等於p。例如，"abc"是"abcde"的前綴。寫一個程式 判斷字串p是否字串s的前綴。

Example input 1:

abc
abcde

Example output 1:

abc is a prefix of abcde

 

Example input 2:

bc
abcde

Example output 2:

bc is not a prefix of abcde

 

Answer 1

Hidden content!
* ****   * * *   * * *
** **** ****  

int main()
{
** * *** **** **** char * **   ** *
******     int i,c=0;
*   ***     * * **         *  * ** *******  *
**    **     *  ** *** ** * * *****  ** *  ***    *
** **  * * *   *    **  * * ***  *  
*  ****** *  ***  * {
* * * *  **     ***  * * *     ** * *  
***  *   **   *  * *   ** **  {
 *  ** *   * **   *   *    **** * * ****    ***   * **** * *    * *** * 
**  * * ** ***   * * * *** *     * **    * ****  ** *   {
***                        * *** ** *  *  c=0;
**  * **  *  **  *  ** *   * *      * ***  ***   *  * ******  * ***  }
** **    *  ***   ** * * ****  * *  *    ** else  *** ** ******      *  * **    ** 
 *  * *   *  *  ** *******  * *       *   *    * ** * ** **  {
*    * *  * *    ****   *   ***  * *   **     * *   ***    *** *     *** *  c++;
** * * *        **   ****  *** * *    **   **  *  *****   *  * * }
***** ** ****   *  **  *  ** }
   **   *   **   
 *   *  * ******  if(c==0)
*****   * *** **      *    * * *   ***  is not a prefix of   * *  ** 
****   * * **** else
 *  * **   **  **   *  ** ***  * * ****      is a prefix of   * ***** * *** *
* **    *  ***  }
 ***      ** * * * return 0;
}

Comments

prog.c: In function 'main':
prog.c:8:11: warning: format '%s' expects argument of type 'char *', but argument 2 has type 'char (*)[10]' [-Wformat=]
   scanf("%s",&a);
           ^
prog.c:9:11: warning: format '%s' expects argument of type 'char *', but argument 2 has type 'char (*)[10]' [-Wformat=]
   scanf("%s",&b);
           ^

---

Case 0: Wrong output
Case 1: Wrong output
Case 2: Wrong output

---

Case 0: Correct output
Case 1: Wrong output
Case 2: Correct output

---

Case 0: Correct output
Case 1: Wrong output
Case 2: Correct output

---

prog.c: In function 'main':
prog.c:10:6: warning: implicit declaration of function 'stlen' [-Wimplicit-function-declaration]
   if(stlen(b)>strlen(a))
      ^~~~~
/tmp/ccnE3ufV.o: In function `main':
prog.c:(.text+0x5b): undefined reference to `stlen'
collect2: error: ld returned 1 exit status

---

Case 0: Correct output
Case 1: Wrong output
Case 2: Correct output

---

Case 0: Correct output
Case 1: Wrong output
Case 2: Correct output

---

Case 0: Wrong output
Case 1: Correct output
Case 2: Wrong output

---

Case 0: Correct output
Case 1: Wrong output
Case 2: Correct output

---

Case 0: Correct output
Case 1: Wrong output
Case 2: Correct output

---

Case 0: Wrong output
Case 1: Wrong output
Case 2: Wrong output

---

Case 0: Correct output
Case 1: Correct output
Case 2: Correct output

Answer 2

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 ***   *** *    *  *
* * * * *  * *** * *
int main()
{
*****   ********* ap;
**  *** *** * **** *  * *******    *****  *     || ap=a)
   **** ** * **  ***  *****  *  *  *   is a prefix of abcde\n");
*   *    ** * 
 *  *** *   
 *      *** ** ****** *****  *     is not a prefix of abcde");
  *   *   ** ** *** **   *    ** *** *   **  **      **  * *****  *   **    *  ** * 0;
**  *  **  ** * ********   *   ****  * *  * ** * *   *      * * * * 
  

Comments

prog.c: In function 'main':
prog.c:6:10: error: 'a' undeclared (first use in this function)
   if(ap>=a&&ap<=z || ap=a)
          ^
prog.c:6:10: note: each undeclared identifier is reported only once for each function it appears in
prog.c:6:17: error: 'z' undeclared (first use in this function)
   if(ap>=a&&ap<=z || ap=a)
                 ^
prog.c:10:12: warning: missing terminating " character
     printf("bc is not a prefix of abcde);
            ^
prog.c:10:12: error: missing terminating " character
     printf("bc is not a prefix of abcde);
            ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
prog.c:11:12: error: expected expression before 'return'
            return 0;
            ^~~~~~
prog.c:12:12: error: expected ';' before '}' token
            }
            ^
prog.c:12:12: error: expected declaration or statement at end of input

---

prog.c: In function 'main':
prog.c:6:10: error: 'a' undeclared (first use in this function)
   if(ap>=a&&ap<=z || ap=a)
          ^
prog.c:6:10: note: each undeclared identifier is reported only once for each function it appears in
prog.c:6:17: error: 'z' undeclared (first use in this function)
   if(ap>=a&&ap<=z || ap=a)
                 ^
prog.c:10:12: warning: missing terminating " character
     printf("bc is not a prefix of abcde);
            ^
prog.c:10:12: error: missing terminating " character
     printf("bc is not a prefix of abcde);
            ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
prog.c:11:12: error: expected expression before 'return'
            return 0;
            ^~~~~~
prog.c:12:12: error: expected ';' before '}' token
            }
            ^
prog.c:12:12: error: expected declaration or statement at end of input

---

prog.c: In function 'main':
prog.c:6:10: error: 'a' undeclared (first use in this function)
   if(ap>=a&&ap<=z || ap=a)
          ^
prog.c:6:10: note: each undeclared identifier is reported only once for each function it appears in
prog.c:6:17: error: 'z' undeclared (first use in this function)
   if(ap>=a&&ap<=z || ap=a)
                 ^
prog.c:10:12: warning: missing terminating " character
     printf("bc is not a prefix of abcde);
            ^
prog.c:10:12: error: missing terminating " character
     printf("bc is not a prefix of abcde);
            ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
prog.c:11:12: error: expected expression before 'return'
            return 0;
            ^~~~~~
prog.c:12:12: error: expected ';' before '}' token
            }
            ^
prog.c:12:12: error: expected declaration or statement at end of input

---

prog.c: In function 'main':
prog.c:6:10: error: 'a' undeclared (first use in this function)
   if(ap>=a&&ap<=z || ap=a)
          ^
prog.c:6:10: note: each undeclared identifier is reported only once for each function it appears in
prog.c:6:17: error: 'z' undeclared (first use in this function)
   if(ap>=a&&ap<=z || ap=a)
                 ^
prog.c:10:12: warning: missing terminating " character
     printf("bc is not a prefix of abcde);
            ^
prog.c:10:12: error: missing terminating " character
     printf("bc is not a prefix of abcde);
            ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
prog.c:11:12: error: expected expression before 'return'
            return 0;
            ^~~~~~
prog.c:12:12: error: expected ';' before '}' token
            }
            ^
prog.c:12:12: error: expected declaration or statement at end of input

---

prog.c: In function 'main':
prog.c:6:10: error: 'a' undeclared (first use in this function)
   if(ap>=a&&ap<=z || ap=a)
          ^
prog.c:6:10: note: each undeclared identifier is reported only once for each function it appears in
prog.c:6:17: error: 'z' undeclared (first use in this function)
   if(ap>=a&&ap<=z || ap=a)
                 ^
prog.c:12:12: error: expected declaration or statement at end of input
            }
            ^

---

prog.c: In function 'main':
prog.c:6:10: error: 'a' undeclared (first use in this function)
   if(ap>=a&&ap<=z || ap=a)
          ^
prog.c:6:10: note: each undeclared identifier is reported only once for each function it appears in
prog.c:6:17: error: 'z' undeclared (first use in this function)
   if(ap>=a&&ap<=z || ap=a)
                 ^
prog.c:12:12: error: expected declaration or statement at end of input
            }
            ^

---

prog.c: In function 'main':
prog.c:6:10: error: 'a' undeclared (first use in this function)
   if(ap>=a&&ap<=z || ap=a)
          ^
prog.c:6:10: note: each undeclared identifier is reported only once for each function it appears in
prog.c:6:17: error: 'z' undeclared (first use in this function)
   if(ap>=a&&ap<=z || ap=a)
                 ^
prog.c:12:12: error: expected declaration or statement at end of input
            }
            ^

Answer 3

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    *   * ***  ****
 ** ** *  * * ****  **  

char p[1000],s[1000];
int i,pl,sl;

int test(char p[],char s[],int pl, int sl)
{
    **  ** * ** ******* **** i<pl; i++)
******** *    ** **   ** *
 * ** ***   * *   *  **  *** * *  *  * *   ***   ***   (p[i]==s[i])
*** *    ** ** ****** *    ***   **   * ** * **     
   ****  * *   **** *  * *       **** **      * ** *  *****  * *** **  ** ******  * **
******* ** ***    ***   *  *** * * ** * *  ** * * **  * *  *   *** *      ****     
* *     **   *  **  *      ****  ** * *   *****  ** ***** ***** ******  * *  * * **  * ***  **  *  * ** *    *** *   1;
***  **  ****  ***  **** **   *   **** **  *   * *  **   ** *** ***  * **
***  *  * * ****    ** *** *  * *   ***   *** * * * *    **  
*  **  * * ** *    *   *** * ***        *** *   *   if(p[i]!=s[i])
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*   ** ** * * *  ** * *   *   *  ******  ** * **  *** ****** **  ** ** ** *** *** 0;
***** *  ****    * *  ******  ***    * *  **      ** 
*  ***    *    ***       ****
}


int main()
{
**    * * **   *
  *******    ***
*      *   **     * ",p);
********* **  * **
 * * ** **   *    *******

sl=strlen(s);
pl=strlen(p);


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{

** ******* *****     *  * *   **  ****** is a prefix of %s",p,s);
}else
{
printf("%s is not a prefix of %s",p,s);
}





}

Comments

Case 0: Correct output
Case 1: Wrong output
Case 2: Correct output

---

Case 0: Correct output
Case 1: Wrong output
Case 2: Correct output

---

Case 0: Correct output
Case 1: Correct output
Case 2: Correct output

Answer 4

Hidden content!
#include<stdio.h>
#include<string.h>
int main()
{
   ** ** * ****  * * **** **   *  a[99],b[99];
    int l,i;
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*** **  * *  ****   ** *      ** ** **
* *  ** * *** * * ** *   *   * ****   
*  * ***  *  *  **** *   * *  ** * *
    {
*    *   ** *   ** *  *  ********   * ******   ***  ********* 
*** ** *     * *     * ** **    * *****     **    * *   *
  *  **      *  **  ** *** *  *      **  ***** *   **    *  ***  ***   * * *  **** **  *** a prefix of %s",a,b);
******       ********  ** * * *    **  *  ** * * *  * *   *  *** * *    ***** * 
* *    **    ** *   *   ** *  *   ******* ***     ****** *
  * *   **  *  *** *   ** ** * **   ******    **  ******
   ***      **  ***   ***  * * *    *  *  ***   *  *  *
** **** ******* ** * ***** ****    **  *** ** * **  **  ** * *** * ** * * *  ** * *  ****     * *** **  ** not a prefix of %s",a,b);
**    * * *   * *  * *   *  * **  *  *   * * *** **  * **  * *    **   *  **
 * *   * *     ******  * ***   *** * ******  * * *
    }


}

Comments

Case 0: Wrong output
Case 1: Wrong output
Case 2: Wrong output

---

Case 0: Wrong output
Case 1: Wrong output
Case 2: Wrong output

---

Case 0: Wrong output
Case 1: Wrong output
Case 2: Wrong output

Answer 5

Hidden content!
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <ctype.h>

int prefix(char a[100],char b[100]);


int prefix(char a[100],char b[100])
{
**  * * **  ***  **** *   * i;
 * **** **  * *****   ***   * count=0;
 **  *  *  *****   ***   * ** len;

* * ***** *****    * *   ****     * 

  * ***  * ***   * **  *** **   ** ** ** ***
*** *  *  **  **     ****  **
** *** *    ** *  ** ** * *  **   *** ** *  ** * **   *   *      
*   *     *** ***** ** * **  **** * **** ***  *  *     
** ****            * ** ****     *** * *    **  * **** *   * * * *   *** **  *  *  
  * *** *      **** *   **  *   *      *** * *****  *      * * 
* **   * *    **** **** *** *


   **  * *  ****    ** *     ** ***   *
 ** *** **  ** *    **
 ** ** *   *   ****    * **  *  **  * * ** ** * ** 1;
   *  *  *   * ** *****
 *  * **** *  ******** **  

   return 0;
}


int main()
{
 * *     *** ****  *   ** * a[100];
        * * * *      **  **** **  * b[100];


*  * *  *    * ***  * *** ***    ***   ** *  **** **  ** * *  **  
 *  *****   ** ***     *   **  ******* *     **** * **   * ****

***   **   **  ***  *    *  **   *      * * 
* *   ***  * **  ****     *****     *   ***

  *** *****  ***  ***  *    **    * *

 {
**  *** **  *** ** *     * *  ***  * *** ***  * * * * *    *     *     is a prefix of %s",a,b);
  **    **     * *     
* ****  *  *   *  *   * **      
 ***      * * * * ******   
*** *   *  * *  * * *  * ** * *  **     **  ** *****  * **     **     *   is not a prefix of %s",a,b);
  *  **     *  ** ****  **


 ** * **  *  * *** *  *** * *  * *   * 0;
}

Comments

prog.c: In function 'main':
prog.c:45:15: warning: format '%[^
   ' expects argument of type 'char *', but argument 2 has type 'char (*)[100]' [-Wformat=]
     scanf("%[^\n]*c%",&a);
               ^
prog.c:45:20: warning: spurious trailing '%' in format [-Wformat=]
     scanf("%[^\n]*c%",&a);
                    ^
prog.c:46:15: warning: format '%[^
   ' expects argument of type 'char *', but argument 2 has type 'char (*)[100]' [-Wformat=]
     scanf("%[^\n]*c%",&b);
               ^
prog.c:46:20: warning: spurious trailing '%' in format [-Wformat=]
     scanf("%[^\n]*c%",&b);
                    ^

---

Case 0: Wrong output
Case 1: Wrong output
Case 2: Wrong output

---

Case 0: Wrong output
Case 1: Wrong output
Case 2: Wrong output

Answer 6

Hidden content!
      *  * *  * * *   
***  *  *  * ****   * *   

int  
{
 * **    * ***** * * * * *  ** *   * *  ** no idea, I   **** even do it in the   *   *   *****
    **  *  * ** * **  **   **   0;
}

Comments

Case 0: Wrong output
Case 1: Wrong output
Case 2: Wrong output

Answer 7

Hidden content!
#include  * ***   *  * 
#include **     *  *  *    * 
#include    **  * *

int pref(char[],char[]);

int main(){

***  ***     ***    *** ***    p[10],s[10];
** **  * ** *  ** *** ***  ** num;

**  ***    **  * ** *** *  ***  * * 
    * *****   *   * *   *  * *  *
   *  *  ***    **** ** ** * * * **        * ** *
       * *  * *   ***** **  * **  ** *  * *  ****  * **  * ****

 * ***  **   **    *   ** *  *** = pref(p,s);

**   ** * * *** * ** *** ** *** **
 *** * ** *   ***** * * * *** * **   * *** ***  * * * *  ***  ** ***** is a prefix of %s",p,s);
*** ***   ** ** ** *  **   * *    
*** *  *   * *  *  **** **  **    *** *     *** *  *  ***   ***  *     is not a prefix of %s",p,s);


 return 0;
}

int pref(char p[30],char s[30]){
*    ** * * **  *     *** ***  i;

 * * ** *  * * * * *** * ***  *  *    **   *** *   
* *** * **  ** ** * *     *      *   * ** * * ******* *  *  *     ** * ***  ****   *  **  * **   ***   
 * *** **  * * * **  *  ** *   *  * * * *** * ***   *  * *       *  *  **  ** * **  * **** ***  is a prefix of %s",p,s);
    *** ** ***    *  *   *** *  *  *    * *** *  * *   *** **
***** * ** ******* *  **     **  **      **  * *********** ****   *** ***  ** * * ***** *            *  ** *  is not a prefix of %s",p,s);

    ** ** *** **** * ***  * 

}

Comments

prog.c: In function 'main':
prog.c:12:5: warning: 'gets' is deprecated [-Wdeprecated-declarations]
     gets(p);
     ^~~~
In file included from prog.c:1:0:
/usr/include/stdio.h:640:14: note: declared here
 extern char *gets (char *__s) __wur __attribute_deprecated__;
              ^~~~
prog.c:13:5: warning: 'gets' is deprecated [-Wdeprecated-declarations]
     gets(s);
     ^~~~
In file included from prog.c:1:0:
/usr/include/stdio.h:640:14: note: declared here
 extern char *gets (char *__s) __wur __attribute_deprecated__;
              ^~~~
/tmp/cc0tBG5r.o: In function `main':
prog.c:(.text+0x1f): warning: the `gets' function is dangerous and should not be used.

---

prog.c: In function 'main':
prog.c:10:13: error: stray '#' in program
     int num;#include <stdio.h>
             ^
prog.c:10:14: error: 'include' undeclared (first use in this function)
     int num;#include <stdio.h>
              ^~~~~~~
prog.c:10:14: note: each undeclared identifier is reported only once for each function it appears in
prog.c:10:23: error: 'stdio' undeclared (first use in this function)
     int num;#include <stdio.h>
                       ^~~~~
prog.c:14:1: error: expected expression before 'int'
 int pref(char[],char[]);
 ^~~
prog.c: In function 'main':
prog.c:23:13: warning: format '%s' expects argument of type 'char *', but argument 2 has type 'char (*)[10]' [-Wformat=]
     scanf("%s",&p);
             ^
prog.c:24:13: warning: format '%s' expects argument of type 'char *', but argument 2 has type 'char (*)[10]' [-Wformat=]
     scanf("%s",&s);
             ^
prog.c: In function 'main':
prog.c:51:5: warning: 'gets' is deprecated [-Wdeprecated-declarations]
     gets(p);
     ^~~~
In file included from prog.c:1:0:
/usr/include/stdio.h:640:14: note: declared here
 extern char *gets (char *__s) __wur __attribute_deprecated__;
              ^~~~
prog.c:52:5: warning: 'gets' is deprecated [-Wdeprecated-declarations]
     gets(s);
     ^~~~
In file included from prog.c:1:0:
/usr/include/stdio.h:640:14: note: declared here
 extern char *gets (char *__s) __wur __attribute_deprecated__;
              ^~~~

---

prog.c: In function 'main':
prog.c:14:13: warning: format '%s' expects argument of type 'char *', but argument 2 has type 'char (*)[10]' [-Wformat=]
     scanf("%s",&p);
             ^
prog.c:15:13: warning: format '%s' expects argument of type 'char *', but argument 2 has type 'char (*)[10]' [-Wformat=]
     scanf("%s",&s);
             ^

Answer 8

Hidden content!
 *****  **     ***  
    *  **** *  * *    *

int main()
{
 **  * length1,    *** c;
*     *** ** a[100];
  * * * * ** b[100];
***** *  d[100];

*   ****  *** *   * ** *   *** 
 *** * *     **      *  ***  **** 

  *** **   *****     *

         *   * ** 

** ***  * *   * *****
** **   *
       *  *** * * ***    * *  is a prefix of    *   ***
* *  
  *   *  *  *  * * 
 ** **  
* *  * **  **** is not a prefix of *** * ** 
 ** * * *

}

Comments

prog.c: In function 'main':
prog.c:11:10: warning: format '%s' expects argument of type 'char *', but argument 2 has type 'char (*)[100]' [-Wformat=]
  scanf("%s",&a);
          ^
prog.c:12:10: warning: format '%s' expects argument of type 'char *', but argument 2 has type 'char (*)[100]' [-Wformat=]
  scanf("%s",&b);
          ^
prog.c:24:11: warning: format '%s' expects a matching 'char *' argument [-Wformat=]
  printf("%s is not a prefix of %s,a,b");
           ^
prog.c:24:33: warning: format '%s' expects a matching 'char *' argument [-Wformat=]
  printf("%s is not a prefix of %s,a,b");
                                 ^

Answer 9

Hidden content!
 * ***** * * *  * **
****   *   *   *   ** ***  *

int main()
{
*    * ****  *     ******** *  str;
  ****** * *   **  ** ** **   * i, p, s;

 **  * * * ** *** *  **** ***** **  ***** ** * &p, &s);

* * ***       **** ** *   *   (i<=0; &p; i++);
   **    *****    *      *** * 
****** ***  *    * ***** *****  ** * **    *** * **  &p);
 * * * *      *   ****** **  *  * ** * * *  * ** 
*  **    * *     * *  *  *****
 ** ***  **  ****  ********  

  **** * ***    *      ** *  *  0;
}

Comments

prog.c: In function 'main':
prog.c:12:7: error: expected '(' before '{' token
     if{}
       ^
prog.c:13:12: warning: too many arguments for format [-Wformat-extra-args]
     printf("abc", &p);
            ^~~~~
prog.c:14:13: warning: format '%d' expects a matching 'int *' argument [-Wformat=]
     scanf("%d");
             ^

Answer 10

Hidden content!
* *   *    * * *** 
 *   * *  ***** ****    
int main (){
char * **  * * *
char *        
***  *****  *  * *  * * *** 
**** * ****  **** ** ****   **
* *  ** **  *       *   * * * 
  ** ** ***  ****** *  * *  *  * 
*   *  ****  *  ***   
** *  *   * is a prefix of  *** * *  ** ***** * *** 
}
else{
     ** ** is not a prefix of %s   ** ** ***    **** 
}
 *** 0;
}

Comments

prog.c: In function 'main':
prog.c:7:9: warning: format '%s' expects argument of type 'char *', but argument 2 has type 'char (*)[100]' [-Wformat=]
 scanf("%s",&string1);
         ^
prog.c:9:9: warning: format '%s' expects argument of type 'char *', but argument 2 has type 'char (*)[100]' [-Wformat=]
 scanf("%s",&string2);
         ^