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);
         ^