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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**  *****  ** ** **** *  *  **  * ** ** *   ** 
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* **** ** * *** * *** *       **    ** *   ***    * *   *    
******* ****  *   *     ** **   **   ****  *    **          ********  * **  *  ** *  ***** * 0;
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}


int main()
{
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*   ***  *  ***   
* * * **  * *    ",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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* ****  * **** * * ** * **     ** *
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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;

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

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


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