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);
         ^