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);
         ^