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);
         ^