Merge pull request #81 from InflixOP/patch1

Patch1

Author: InflixOP

#1137. N-th Tribonacci Number.cpp

@@ -0,0 +1,13 @@
+class Solution {
+    public:
+        int tribonacci(int n) {
+            vector<int> dp(n+1,0);
+            if(n>=1)
+            dp[1]=1;
+            if(n>=2)
+            dp[2]=1;
+            for(int i=3;i<=n;i++)
+            dp[i]=dp[i-1]+dp[i-2]+dp[i-3];
+            return dp[n];
+        }
+    };

#746. Min Cost Climbing Stairs.cpp

@@ -0,0 +1,15 @@
+class Solution {
+    public:
+        int minCostClimbingStairs(vector<int>& cost) {
+            int n=cost.size();
+            vector<int> dp(n,0);
+            dp[0]=cost[0];
+            dp[1]=cost[1];
+            for(int i=2;i<n;i++){
+                int l=dp[i-1]+cost[i];
+                int r=dp[i-2]+cost[i];
+                dp[i]=min(l,r);
+            }
+            return min(dp[n-1],dp[n-2]);
+        }
+    };