Minimum Path Sum

算法不多说，动态规划很典型。具体的实现比较好，将二维的动态规划使用一个一维数组就解决了。

class Solution {
public:
int minPathSum(vector<vector<int> > &grid) {
if(grid.size() == 0)
return 0;
vector<int> DP(grid[0].size(), 0);
DP[0] = grid[0][0];
for (int i = 1; i < grid[0].size(); ++i)
DP[i] = DP[i - 1] + grid[0][i];
for (int i = 1; i < grid.size(); ++i) {
for (int j = 0; j < grid[0].size(); ++j) {
if (j == 0) {
DP[j] += grid[i][j];
}
else {
DP[j] = min(DP[j], DP[j - 1]) + grid[i][j];
}
}
}
return DP[grid[0].size() - 1];
}
};
http://oj.leetcode.com/problems/minimum-path-sum/