Project Euler Problem 31

问题：

In England the currency is made up of pound, £, and pence, p, and there are eight coins in general circulation:

1p, 2p, 5p, 10p, 20p, 50p, £1 (100p) and £2 (200p).

It is possible to make £2 in the following way:

1£1 + 150p + 220p + 15p + 12p + 31p

How many different ways can £2 be made using any number of coins?

答案：73682

#include

int m[8]={1,2,5,10,20,50,100,200};

int methods(int n, int *m, int len)
{
    if (len == 1)
        return 1;
    else {
        int k = n / m[len-1];
        int sum=0;
        int i = 0;

        for (i=0; i<=k; i++)
            sum += methods (n-m[len-1]*i, m, len-1);
        return sum;
    }
}

int main(void)
{
    int count=0;
    count = methods (200, m, 8);
    printf("%d\n", count);

    return 0;

}