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);
         ^