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