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;
**  *   *   * *  ** **     * ***    *** ** * ****
  *** * *   * **  **  **   **** * ** *******
   *   **  *  * **** **   * * ** *** 
 *   **  ** ** {
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    **  * *   *  **  * ***    *  * ** *  **** *    *  ***  *   
 ** *  * *  * *  *    ** **      * *    ** **           {
     ** **                *  ** *  * **  *  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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 **** * * *          * * ******
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* *     *** *  ** ****    **         ** * * ** ***  * ** *  *    *  ** **   **
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***** *  * * **  * *    * *** *    * **  **  *       **** *  ***  ** *** **       * 
 *  ** * ***  * *   * ** *  *  **  ******* **    *  *  * **
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****  * * **   *** *   ** * **    **  ** * ** *  *     
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**    ***** *  ***   *   *   **
}


int main()
{
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  ** ***   *  *
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  **  *   **** * *  * 
     ** ** * ** *** ** **

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