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);
         ^