more clean implementation

Author: haoel

algorithms/cpp/minimumPathSum/minimumPathSum.cpp

@@ -27,27 +27,18 @@
 #include <vector>
 using namespace std;
 
-int minPathSum(vector<vector<int> > &grid) {
-    if (grid.size()<=0){
-        return 0;
-    }
-    int i, j;
-    for(i=0; i<grid.size(); i++){
-        for(j=0; j<grid[i].size(); j++){
-            int top = i-1<0 ? INT_MAX : grid[i-1][j] ;
-            int left = j-1<0 ? INT_MAX : grid[i][j-1];
-            if (top==INT_MAX && left==INT_MAX){
-                continue;
-            }
-            grid[i][j] += (top < left? top: left);
-
+int minPathSum(vector<vector<int>>& grid) {
+    for (int i=0; i<grid.size(); i++) {
+        for (int j=0; j<grid[0].size(); j++) {
+            if (i==0 && j==0) continue;
+            else if (i==0) grid[0][j] += grid[0][j-1];
+            else if (j==0) grid[i][0] += grid[i-1][j];
+            else grid[i][j] += min( grid[i-1][j], grid[i][j-1]);
         }
     }
-
     return grid[grid.size()-1][grid[0].size()-1];
 }
 
-
 int main()
 {
     int a[6][2]={{7,2},{6,6},{8,6},{8,7},{5,0},{6,0}};
@@ -59,7 +50,7 @@ int main()
         }
         grid.push_back(v);
     }
-    
+
     cout << "minPathSum=" << minPathSum(grid) << endl;
 
     return 0;