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);
         ^