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);
         ^