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);
         ^