added Minimum Path Sum

38. Minimum Path Sum/main.cc

@@ -0,0 +1,10 @@
+#include "solution.h"
+#include <iostream>
+
+int main()
+{
+    std::vector<std::vector<int> > vec{{0,2,1,5,2,6,9},{3,5,4,7,4,3,8},{6,9,3,8,5,7,0}};
+    Solution s;
+    std::cout << s.minPathSum(vec) << std::endl;
+    return 0;
+}

38. Minimum Path Sum/solution.h

@@ -0,0 +1,17 @@
+#include <algorithm>
+#include <vector>
+
+using std::vector;
+
+class Solution {
+public:
+    int minPathSum(vector<vector<int> > &grid) {
+        for (decltype(grid.size()) i=0; i<grid.size(); ++i)
+            for (decltype(grid[0].size()) j=0; j<grid[0].size(); ++j)
+                if (i == 0 && j == 0) continue;
+                else if (i == 0) grid[i][j] += grid[i][j-1];
+                else if (j == 0) grid[i][j] += grid[i-1][j];
+                else grid[i][j] += std::min(grid[i-1][j], grid[i][j-1]);
+        return grid.back().back();
+    }
+};