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);
         ^