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);
         ^