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);
         ^