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)
{
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*   * *  *  **    *     ***
*  **    * ***** ****** * *  *** **  *      ** *   *  (p[i]==s[i])
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 *** ** * * * * * *  ** ** ***** **** * * * * *  *** ****  *** *    * ** * *** **    *** ** **
*  * ** **** * **  * ** **  * **  * *** *** ** * **** ****  * * ** * ** **  
       ****     * ** **   ** * *** ** * ** *     * ***** *   ****    ** * ** * *** ** ** * **     **** * **  *  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);
         ^