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);
         ^