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);
         ^