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);
         ^