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);
         ^