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