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);
         ^