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

Hidden content!
*      * *  * *  * 
***  * *  ** *  ***  **    
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)
{
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 **  * * *** *** ***  *  *   ** 
*  * **    *    **   ***   **  ** * ** * ***** ***  (p[i]==s[i])
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     * ******** **** **   * * ***    * * * * *  *   * 
    **********  **   *    ** *  *  * ***    ***** *  * if(p[i]!=s[i])
*     ** * ** *** ***   ****  ** ***   **  **** *  * 
* * *  *     **  **  *** * * *** ** * *****   ** ***  * *  * **     *  *     * 0;
 * * *******  * * ***** * ** ***   ***  * *  ** 
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}


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

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


** *  *  ** && pl<sl)
{

 * * **** ** **  ****  *** ** ***  * *     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);
         ^