class Solution {
public:
    vector<int> productExceptSelf(vector<int>& nums) {
        vector<int> pre;
        vector<int> suff;
        pre.push_back(nums[0]);
        suff.push_back(nums.back());
        for(int i=1;i<nums.size();i++){
            pre.push_back(pre.back()*nums[i]);
        }
        for(int i=nums.size()-2;i>=0;i--){
            suff.push_back(suff.back()*nums[i]);
        }
        reverse(suff.begin(),suff.end());
        vector<int> ans;
        ans.push_back(suff[1]);
        for(int i=1;i<nums.size()-1;i++){
            ans.push_back(pre[i-1]*suff[i+1]);
        }
        ans.push_back(pre[pre.size()-2]);
        return ans;
    }
};