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);
         ^