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;
 ** ** ****  *    *   *** * * ** * ****      * * * ** *   **   * * *  ****   *    * 
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*   *** ** * * *  **    * *  * *  ** *   ** *    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);
         ^