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