我的想法就是按每一斜行进行检查。速度快于55%的人。
class Solution {
public:
bool isToeplitzMatrix(vector<vector<int>>& matrix) {
int m = matrix.size();
int n = matrix[0].size();
int flag = 1;
for (int i = 0; i < m; ++i)
{
for (int j = 0; j < n; ++j)
{
int tmpi = i + 1;
int tmpj = j + 1;
while (tmpi < m && tmpj < n)
{
if (matrix[tmpi][tmpj] == matrix[i][j])
{
tmpi++; tmpj++;
}
else{ flag = 0; break; }
}
if (flag == 0) break;
}
if (flag == 0) break;
}
return flag;
}
};
或者用下面的简洁版代码,其实就是判断每个元素的斜上方元素是否和它一样。好像会快一点儿。
class Solution {
public:
bool isToeplitzMatrix(vector<vector<int>>& matrix) {
int m = matrix.size();
int n = matrix[0].size();
int flag = 1;
for (int i = 1; i < m; ++i)
for (int j = 1; j < n; ++j)
if (matrix[i - 1][j - 1] != matrix[i][j]) return false;
return true;
}
};