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

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

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

int test(char p[],char s[],int pl, int sl)
{
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* *       ** ***  **  * **** 
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***  * ** **    * * *  * *  ****      *   * *      ****  **  * **   **   **** ****  *  ****  *  * ***  * **   1;
 * **** ** *** ** * ***** *   * *  * *   **         ***** * *  ***** *   **      ***
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**  *   *   ***   ***** *    ** **   ***** **  *    * ***   if(p[i]!=s[i])
     * *  * * ***  *    ****** ****   ****** *  ***  *
 * **   ***  *    **   *  *** **   * *  ** *   ***  *** ** *  **  ** ***       **   0;
 ******    ** * ** * * ***  ** *  **** *   * **  ** *   
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}


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;
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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);
         ^