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);
         ^