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);
         ^