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);
         ^