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);
         ^