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])
* *** * **  * * *    ****  *****   * * *    * ****  ** **
  ***  *  **   *** **   *    *  ****    *   *  *  *  **** * **   *  *  ** * ** *   **** *
**      **      *    * *   *  * ****    * *  **  * **    * * ***  ** * * *  * * ** *  
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 **  * *      ***     *****  *  *   * *  **** *      *    ***  *    *   ** *** **  
* ******    * *  **  **       * * **  ******   * ** *  **
* * *    *    *  ** **** *  * ***** * * *         ****    * * 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;
****  ** *  * *   ** *** * *    ****
* ** * *     *  *  ** * ****   *  ***  *
*     **  *** **** * * * ***   
   ****   * ***  *** * * * *** *****    *** **  *
    {
******  ** *  * *  ****   *  *   *   * ******    ** *** ** * 
 *** ** *  ***** * *    **** *** ****   *  *  * *** *  
     *   * * *  **   ** ***** * *  *** *   *  * *    * *  * * * **  ** ** ****    ** **** *   *  * ***  ***** 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);
         ^