Update Solution2.cpp

Author: yanglbme

solution/0700-0799/0746.Min Cost Climbing Stairs/Solution2.cpp

@@ -1,12 +1,11 @@
 class Solution {
 public:
     int minCostClimbingStairs(vector<int>& cost) {
-        int f = 0, g = 0;
-        for (int i = 2; i <= cost.size(); ++i) {
-            int gg = min(f + cost[i - 2], g + cost[i - 1]);
-            f = g;
-            g = gg;
+        int n = cost.size();
+        vector<int> f(n + 1);
+        for (int i = 2; i <= n; ++i) {
+            f[i] = min(f[i - 2] + cost[i - 2], f[i - 1] + cost[i - 1]);
         }
-        return g;
+        return f[n];
     }
-};
+};