给出三角形排列的二维数组,找到从上到下的路径中最小和
2017-05-01 本文已影响25人
敲一手烂代码
// 5.1
// Given a triangle, find the minimum path sum from top to bottom. Each step you may move to adjacent numbers on the row below.
// For example, given the following triangle
// [
// [2],
// [3,4],
// [6,5,7],
// [4,1,8,3]
// ]
// The minimum path sum from top to bottom is 11 (i.e., 2 + 3 + 5 + 1 = 11).
public int minimumTotal(List<List<Integer>> triangle) {
List<Integer> lastRowList = triangle.get(triangle.size() - 1);
int[] dp = new int[lastRowList.size()];
for (int i = 0; i < dp.length; i++) {
dp[i] = lastRowList.get(i);
}
for (int i = triangle.size() - 2; i >= 0; i--) {
for (int j = 0; j < triangle.get(i).size(); j++) {
dp[j] = Math.min(dp[j], dp[j + 1]) + triangle.get(i).get(j);
}
}
return dp[0];
}