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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*** ** * ** ***  * * **       ***  **  
****    * **  * {
*   *** * * * *** **  * * * *  
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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

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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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* ** **   ****   **  *** ****   
**          * * *  *   *    **** *     ****   ** *  * ***     *  (p[i]==s[i])
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*** * *******  * * *        * **    *      *   *** * *  * ** *  * * * *    *  
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}


int main()
{
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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()
{
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    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])
{
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 * ***    ** *      ** * * * 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);
         ^