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);
         ^