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);
         ^