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);
         ^