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);
         ^