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);
         ^