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])
**  ***** ******     *  **   * *  ** ***  *   ***   * ***  *
 **   ***** *** **  *** **  * *  ***  ****** *  ****** *     **** ** * *   *  **        
******  *** ** ***  *  ** **  **  **   *  *** *  *** ** * * ** ***   * **  *
*****    * * * * ***  *** *     * **** *  * ***** **  *  *   ***  *   **      ** *  *    ******   ***    1;
* *  ** *   * * * **  *  ** *  * *  * ** **   *  **  *   ** *  *** ** ***  *** * * *  *  *
*** * * ** *   ******* ** * ****** * *** *   *  *   ** 
   * * *  * ***  *   * * ** **  * **** *         *  ***   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);
         ^