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)
{
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*** * * **** * * * ** * *   *  
** **  **   *   **** ** *        *** ***   * * *  * * **   * * (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);
         ^