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);
         ^