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;
**       *  ***    ** *     **  ** * * ** ** ** * *
*  ****    * * *  **    ***   *** * ***   
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    **  *    **   {
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 * **  *  ***  *    **    ****   ** ***  *  * *  *   * **   *  * **  **** 
**            *    * *  **  **      * * ** *  ****   {
  **                 *** * *  **  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

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*  ****  ** ***    *
** * ** ****  ****** *
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

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 * * ** *** * **
*** ** *   *  **** *

char p[1000],s[1000];
int i,pl,sl;

int test(char p[],char s[],int pl, int sl)
{
* *    *   ***   ****  **  * * i<pl; i++)
*   ** ***** **  ** *********
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* ****   *** *   *     *   ****    *   ** * *** *    *     **   ** *  ** ***  *
* **  *   ** * ** *      * * ***  * *   *    *   * *
*   ****  ** * **  ***** ** * *  *** **  * *    * * * if(p[i]!=s[i])
***  * ******   ** **** *   *** ** ** *  *  *  * *
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}


int main()
{
*  *  * * *   **
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**        * * * *  
 ** ** ****  *  **   **

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