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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*   * * *****  **    *  ** **
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*  ****    * **** *       ** *****   **  * 
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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);


*  *   * * **   * && 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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**  * * **** * * ******  * ** * ***** *  * 
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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])
{
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    * *** ** ***  *  *  ***** count=0;
****   *  ****   ** **  ** **** len;

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

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


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