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