【前缀和】238. 除自身以外数组的乘积

class Solution {
    public int[] productExceptSelf(int[] nums) {
        int n=nums.length;
        int[] f=new int[n];//f[i]为从[0,i-1]的乘积
        int[] g=new int[n];//g[i]为从[i+1,n-1]的乘积
        int[] answer=new int[n];
        f[0]=1;
        g[n-1]=1;
        for(int i=1;i<n;i++){
            f[i]=f[i-1]*nums[i-1];
            System.out.print(f[i]+" ");
        }

         for(int i=n-2;i>=0;i--){
            g[i]=g[i+1]*nums[i+1];
            System.out.print(g[i]+" ");
        }
        for(int i=0;i<n;i++){
            answer[i]=f[i]*g[i];
        }
        return answer;
    }
}