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);
         ^