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Author: assassint2017

Fibonacci Number/Fibonacci_Number.cpp

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+// Runtime: 0 ms, faster than 100.00% of C++ online submissions for Fibonacci Number.
+// Memory Usage: 8.3 MB, less than 43.29% of C++ online submissions for Fibonacci Number.
+
+class Solution 
+{
+public:
+    int fib(int n) 
+    {
+        if (n <= 1) return n;
+
+        int res, lres = 1, llres = 0;
+        for (int i = 2; i <= n; ++i)
+        {
+            res = lres + llres;
+            llres = lres;
+            lres = res;
+        }
+        return res;     
+    }
+};