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

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

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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  * ****** *   * **  * * **  ******* *  **** *   *****   ** ** * *  **  ***  ** ** * * **  *  ** *  *      *** * **  *  1;
 *  * *** * **    *****   * * * *** *  * ** *  *  **  *  * *   **   *  * * *  
**  **    * ***   ****** **  *     *****     *   **  
 ***    ** *  **    **** **  *  *  *  *   * *** if(p[i]!=s[i])
 *     *  * * ** * * * *   ***    ** ** ** *   * **   ** *  
* *   *********   ** **    * *** *  **** *** ****** ** **    ** ****  *   * ** *    ** * **** 0;
    *    **  *      * ** ***  **  *      *** *  **** 
** *  *  *    *  ******  * 
}


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);
         ^