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);
         ^