题解 | #矩阵的最小路径和#

class Solution {
  public:
    /**
     *
     * @param matrix int整型vector<vector<>> the matrix
     * @return int整型
     */
    int minPathSum(vector<vector<int> >& matrix) {
        int n = matrix.size();
        int m = matrix[0].size();
        vector<vector<int> > dp(n + 1, vector<int>(m + 1, 0));
        for (int i = 1; i < n + 1; i++) {
            dp[i][1] = matrix[i - 1][0] + dp[i - 1][1];
        }
        for (int j = 1; j < m + 1; j++) {
            dp[1][j] = matrix[0][j - 1] + dp[1][j - 1];
        }// 初始化值
        for (int i = 2; i < n + 1; i++) {
            for (int j = 2; j < m + 1; j++) {
                dp[i][j] = min(dp[i - 1][j], dp[i][j - 1])
                           + matrix[i - 1][j - 1];
            }
        }
        return dp[n][m];
    }
};