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)
{
*    *      *** ** ** ***  ***  *     i<pl; i++)
 * * *    **   **  ****  **
 *  ***   *  ***  *  **   *** ** *  ** **  * *   **** (p[i]==s[i])
* *         ** *  *** *  * ******  *  ** *   
*   **  **  **  ********   **  *      ** **   ** *  **    *    *  *      ** **  *    **** *   * 
  **   *  *** * ** *** **   *  ***  ****   ***  **  * * * **  *  * *    * **  
  *   * *  * *    * *   *   ***        * *    **    * *     * *      ****   * * * * *  ** *  *** ***    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);
         ^