rt，比赛的官方数据应该是过了，但是民间数据 WA 了三个点，讨论版和提交记录暂时没有看到类似的错误。

因为不想写分讨，就直接贪心选出可选范围内最大/最小的正负值以及 0，多建了几个 st 表来实现这个思路。

#include <iostream>
#define int long long
using namespace std;

const int MAXN = 1e5 + 7;

int n, m, q, cnt1, cnt2;
int l1, r1, l2, r2;
int aa[MAXN], bb[MAXN], Log[MAXN];
int ax[MAXN], bx[MAXN];

int maxx(int x, int y)
{
	if (x * y == 0)
		return x + y;
	return max(x,  y);
}

int minn(int x, int y)
{
	if (x * y == 0)
		return x + y;
	return min(x,  y);
}

struct node
{
	int nmax, nmin, pmax, pmin, ze;
} a[MAXN][30], b[MAXN][30];

signed main()
{
	cin >> n >> m >> q;
	
	Log[0] = -1;
	for (int i = 1; i <= n; i ++)
		Log[i] = Log[i >> 1] + 1;
	
	for (int i = 1; i <= n; i ++)
	{
		cin >> aa[i];
		if (aa[i] == 0)
			a[i][0].ze = 1;
		else if (aa[i] > 0)
			a[i][0].pmax = a[i][0].pmin = aa[i];
		else
			a[i][0].nmax = a[i][0].nmin = aa[i];
	}
	for (int i = 1; i <= m; i ++)
	{
		cin >> bb[i];
		if (bb[i] == 0)
			b[i][0].ze = 1;
		else if (bb[i] > 0)
			b[i][0].pmax = b[i][0].pmin = bb[i];
		else
			b[i][0].nmax = b[i][0].nmin = bb[i];
	}
	
	for (int j = 1; j <= Log[n]; j ++)
		for (int i = 1; i + (1 << j) - 1 <= n; i ++)
		{
			a[i][j].ze = max(a[i][j - 1].ze, a[i + (1 << (j - 1))][j - 1].ze);
			a[i][j].nmax = maxx(a[i][j - 1].nmax, a[i + (1 << (j - 1))][j - 1].nmax);
			a[i][j].nmin = minn(a[i][j - 1].nmin, a[i + (1 << (j - 1))][j - 1].nmin);
			a[i][j].pmax = maxx(a[i][j - 1].pmax, a[i + (1 << (j - 1))][j - 1].pmax);
			a[i][j].pmin = minn(a[i][j - 1].pmin, a[i + (1 << (j - 1))][j - 1].pmin);
		}
	
	for (int j = 1; j <= Log[m]; j ++)
		for (int i = 1; i + (1 << j) - 1 <= m; i ++)
		{
			b[i][j].ze = max(b[i][j - 1].ze, b[i + (1 << (j - 1))][j - 1].ze);
			b[i][j].nmax = maxx(b[i][j - 1].nmax, b[i + (1 << (j - 1))][j - 1].nmax);
			b[i][j].nmin = minn(b[i][j - 1].nmin, b[i + (1 << (j - 1))][j - 1].nmin);
			b[i][j].pmax = maxx(b[i][j - 1].pmax, b[i + (1 << (j - 1))][j - 1].pmax);
			b[i][j].pmin = minn(b[i][j - 1].pmin, b[i + (1 << (j - 1))][j - 1].pmin);
		}
	
	while (q --)
	{
		cnt1 = cnt2 = 0;
		cin >> l1 >> r1 >> l2 >> r2;
		
		int ze, nmax, nmin, pmax, pmin, lg, ans = 0;
		
		lg = Log[r1 - l1 + 1];
		ze = max(a[l1][lg].ze, a[r1 - (1 << lg) + 1][lg].ze);
		nmax = maxx(a[l1][lg].nmax, a[r1 - (1 << lg) + 1][lg].nmax);
		nmin = minn(a[l1][lg].nmin, a[r1 - (1 << lg) + 1][lg].nmin);
		pmax = maxx(a[l1][lg].pmax, a[r1 - (1 << lg) + 1][lg].pmax);
		pmin = minn(a[l1][lg].pmin, a[r1 - (1 << lg) + 1][lg].pmin);
		
//		printf("%d %d %d %d %d %d\n", lg, ze, nmax, nmin, pmax, pmin);
		
		if (ze) ax[++ cnt1] = 0;
		if (nmax) ax[++ cnt1] = nmax;
		if (nmin) ax[++ cnt1] = nmin;
		if (pmax) ax[++ cnt1] = pmax;
		if (pmin) ax[++ cnt1] = pmin;
		
		lg = Log[r2 - l2 + 1];
		ze = max(b[l2][lg].ze, b[r2 - (1 << lg) + 1][lg].ze);
		nmax = maxx(b[l2][lg].nmax, b[r2 - (1 << lg) + 1][lg].nmax);
		nmin = minn(b[l2][lg].nmin, b[r2 - (1 << lg) + 1][lg].nmin);
		pmax = maxx(b[l2][lg].pmax, b[r2 - (1 << lg) + 1][lg].pmax);
		pmin = minn(b[l2][lg].pmin, b[r2 - (1 << lg) + 1][lg].pmin);
		
//		printf("%d %d %d %d %d %d\n", lg, ze, nmax, nmin, pmax, pmin);
		
		if (ze) bx[++ cnt2] = 0;
		if (nmax) bx[++ cnt2] = nmax;
		if (nmin) bx[++ cnt2] = nmin;
		if (pmax) bx[++ cnt2] = pmax;
		if (pmin) bx[++ cnt2] = pmin;
		
//		for (int i = 1; i <= cnt1; i ++)
//			cout << ax[i] << ' ';
//		cout << '\n';
//		
//		for (int i = 1; i <= cnt2; i ++)
//			cout << bx[i] << ' ';
//		cout << '\n';
		
		ans = ax[1] * bx[1];
		
		for (int i = 1; i <= cnt1; i ++)
		{
			int tmp = ax[i] * bx[1];
			for (int j = 2; j <= cnt2; j ++)
				tmp = min(tmp, ax[i] * bx[j]);
			
			if (i == 1)
				ans = tmp;
			else
				ans = max(ans, tmp);
		}
			
		cout << ans << '\n';
	}
	
	return 0;
}