Given a m x n grid filled with non-negative numbers, find a path from top left to bottom right which minimizes the sum of all numbers along its path.
Note: You can only move either down or right at any point in time.
class Solution {
public:
int minPathSum(vector<vector<int> > &grid) {
int result = 0;
int m = grid.size();
if (m < 1)
{
return result;
}
int n = grid[0].size();
int buf[m][n];
buf[0][0] = grid[0][0];
for (int i = 1; i < n; i++)
{
buf[0][i] = buf[0][i-1] + grid[0][i];
}
for (int j = 1; j < m; j++)
{
buf[j][0] = buf[j-1][0] + grid[j][0];
}
for (int i = 1; i < m; i++)
{
for (int j = 1; j < n; j++)
{
buf[i][j] = min(buf[i-1][j], buf[i][j-1]) + grid[i][j];
}
}
return buf[m-1][n-1];
}
};