在行列都排好的矩阵中找数

• 在行列都排好的矩阵中找数

题目来源

• 题目思路

• C++代码实现

#include <vector>
#include <iostream>
using namespace std;

class Solution
{
public:
	bool IsExist(vector<vector<int>>& matrix, int k)
	{
		bool existence = false;

		int row = matrix.size();
		int col = matrix[0].size();

		int a = 0;
		int b = col - 1;

		while (a < row && b >= 0)
		{
			if (matrix[a][b] > k)
			{
				b--;
			}
			else if (matrix[a][b] < k)
			{
				a++;
			}
			else if (matrix[a][b] == k)
			{
				existence = true;
				break;
			}
		}

		return existence;
	}
};

int main()
{
	int n = 0;
	int m = 0;
	int k = 0;
	cin >> n;
	cin >> m;
	cin >> k;

	vector<vector<int>> matrix(n, vector<int>(m));
	for (int i = 0; i < n; i++)
	{
		for (int j = 0; j < m; j++)
		{
			cin >> matrix[i][j];
		}
	}
	Solution s;
	if (s.IsExist(matrix, k))
	{
		cout << "Yes";
	}
	else
	{
		cout << "No";
	}
	return 0;
}