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);
         ^