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);
         ^