/**

public static void main(String[] args) throws Exception {

int[] coins = {1, 2, 5};

System.out.println(new CoinChange2().change(5, coins));

}

public int change(int amount, int[] coins) {

int[][] dp = new int[coins.length][amount + 1];

for (int i = 0, l = coins.length; i < l; i++) Arrays.fill(dp[i], -1);

return dp(dp, 0, coins, coins.length, amount);

}

private int dp(int[][] dp, int i, int[] coins, int l, int n) {

if (n == 0) return 1;

else if (i >= l) return 0;

if (n < 0) return 0;

if (dp[i][n] != -1) return dp[i][n];

dp[i][n] = dp(dp, i + 1, coins, l, n) + dp(dp, i, coins, l, n - coins[i]);

return dp[i][n];

}