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);
         ^