Write a program for a matchstick game being played between the computer and a user. Your program should ensure that the computer always wins. Rules for the game are as follows: -There are 21 matchsticks. -The computer asks the player to pick 1, 2, 3 or 4 matchsticks. -After the person picks, the computer does its picking. -Whoever is forced to pick up the last matchstick loses the game.

-There are 21 matchsticks.
-Whoever is forced to pick up the last matchstick loses the game.
So the last one is special, so it's all about how to get rid of 20 matches in pairs of turns.

-The computer asks the player to pick 1, 2, 3 or 4 matchsticks.
So if we reduce the total by 5 each round, the sequence will go
21 16 11 6 1
In effect, whatever number the user picks (n), the computer picks 5-n

#include<stdio.h>
main()
{

int matchsticks=21, user, computer;

printf("Do not enter Invalid Numbers.\nNumbers above 4 are invalid.");

printf("\nIf you do so, the computer automatically wins.");

while (matchsticks>=1)
{

printf("\nNumber of matchsticks available right now is %d.", matchsticks);

printf("\n\nYour Turn...\n\n\n");

printf("\nPick up the matchstick(s)-- (1-4): ");
scanf ("%d", &user);

if (user>4)

{
printf("Invalid Selection");
break;
}

computer=5-user;

printf("\nComputer's Turn..\n" );
printf("\nComputer chooses:%d", computer);

matchsticks=matchsticks-user-computer;
continue;

if(matchsticks==1)

break;
}

matchsticks--;
printf("\nComputer Wins");

}