class Solution {
public:
    int Fibonacci(int n) {
        if(n == 1 || n == 2) {
            return 1;
        }
        vector<int> dp(n + 1);
        dp[0] = 0;
        dp[1]= 1;
        dp[2]= 1;
        
        
        for (int i = 2; i <= n; i++) {
            dp[i] = dp[i - 1] + dp[i- 2];
        }
        return dp[n];
    }
};