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);
         ^