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);
         ^