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);
         ^