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);
         ^