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


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