蠢方法（暴力）

#include <bits/stdc++.h>
using namespace std;
const int N = 1e7 + 10;
const int INF = 0x3f3f3f3f;
int n;
long long a[N],dpm[N],dpn[N],nmax = -INF,nmin = INF;
int main(){
	cin >> n;
	for(int i = 1;i <= n;i++){
		cin >> a[i];
	}
	dpn[0] = dpm[0] = 1;
	for(int i = 1;i <= n;i++){
		dpm[i] = a[i];
		dpm[i] = max(a[i],dpm[i - 1] * a[i]);
		dpn[i] = a[i];
		dpn[i] = min(a[i],dpn[i - 1] * a[i]);
		dpm[i] = max(dpm[i],dpn[i - 1] * a[i]);
		dpn[i] = min(dpn[i],dpm[i - 1] * a[i]);
		//printf("dpm[%d] = %d\n",i,dpm[i]);
		//printf("dpn[%d] = %d\n",i,dpn[i]);
		nmax = max(nmax,dpm[i]);
		nmin = min(nmin,dpn[i]);
	}
	cout << nmax << endl << nmin;
	return 0;
}