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);
         ^