/**

public int cuttingRope(int n) {

int[] dp = new int[n + 1];

// dp[0] = 0;

// dp[1] = 0;

// from down to up.

for (int i = 2; i <= n; i++) {

// just need loop to i / 2.

int mid = i >> 1;

// state transition equation is f(i) = max(f(j) + f(i - j)).

for (int j = 1; j <= mid; j++) {

// divide current string to two parts,

// and calculate product what current can be get most.

// Math.max(dp[j], j) is mean cut current length j string or don't.

int product = Math.max(dp[j], j) * Math.max(dp[i - j], i - j);

dp[i] = Math.max(dp[i], product);

}

}

return dp[n];

}