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);
         ^