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);
         ^