简单的钱币兑换

#include <bits/stdc++.h>
using namespace std;
const int MAXN = 33000;
long long dp[MAXN] = {0};


int main () {
    dp[0] = 1;
    for (int i = 1; i <= 3; i++) {
        for (int j = i; j < MAXN; j++) {
            dp[j] += dp[j-i];
        }
    }
    int n;
    while(~scanf("%d", &n)){
        printf("%I64d\n", dp[n]);
    }
    return 0;
}