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);
         ^