class Solution {
public:
    vector<int> productExceptSelf(vector<int>& nums) {

        int n = (int)nums.size();
        vector<int>pre(n,1);
        int prod = 1;

        for(int i=1;i<n;i++)
        {
            pre[i]  = pre[i-1] * nums[i-1];
        }

        for(int i=n-1; i>=0; i--)
        {
            pre[i] = pre[i] * prod;
            prod *= nums[i];
        }

        return pre;
    }
};