c_cpp 搜索2D Matrixhttp：//oj.leetcode.com/problems/search-a-2d-matrix/

Posted 2021-05-14

class Solution {
public:
    bool searchMatrix(vector<vector<int> > &matrix, int target) {
        int m = matrix.size();
        if(m == 0){
            return false;
        }
        int n = matrix[0].size();
        int front_row = 0;
        int back_row = m - 1;
        int mid_row = -1;
        while(front_row <= back_row){
            mid_row = (front_row + back_row) / 2;
            if(matrix[mid_row][0] > target){
                back_row = mid_row - 1;
                continue;
            }
            else if(matrix[mid_row][n - 1] < target){
                front_row = mid_row + 1;
                continue;
            }
            else{
                break;
            }
        }
        if(front_row > back_row){
            return false;
        }
        int front_col = 0;
        int back_col = n - 1;
        while(front_col <= back_col){
            int mid_col = (front_col + back_col) / 2;
            if(matrix[mid_row][mid_col] == target){
                return true;
            }
            else if(matrix[mid_row][mid_col] > target){
                back_col = mid_col - 1;
                continue;
            }
            else {
                front_col = mid_col + 1;
                continue;
            }
        }
        if(front_col > back_col){
            return false;
        }
    }
};