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);
         ^