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);
         ^