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);
         ^