Submission #257404

#	Time	Username	Problem	Language	Result	Execution time	Memory
257404		dolphingarlic	Abduction 2 (JOI17_abduction2)	C++14	100 / 100	3089 ms	257640 KiB

abduction2

#include <bits/stdc++.h>
typedef long long ll;
using namespace std;

map<tuple<int, int, int>, ll> dp;
int n, m, h[50001][16], v[50001][16];

ll dfs(int x, int y, int dir) {
	if (dp.count({x, y, dir})) return dp[{x, y, dir}];
	ll &ans = dp[{x, y, dir}];
	if (dir & 1) { // Up or down (x changes)
		int sign = dir - 2;
		int nxt_x = x;
		for (int i = 15; ~i; i--) {
			int tmp_x = nxt_x + (1 << i) * sign - sign;
			if (tmp_x < 1 || tmp_x > n) continue;
			if ((sign == 1 ? h[nxt_x][i] : h[tmp_x][i]) > v[y][0]) continue;
			nxt_x = tmp_x + sign;
		}
		if (nxt_x < 1 || nxt_x > n) return ans = abs(nxt_x - sign - x);
		return ans = abs(nxt_x - x) + max(dfs(nxt_x, y, 0), dfs(nxt_x, y, 2));
	} else { // Left or right (y changes)
		int sign = dir - 1;
		int nxt_y = y;
		for (int i = 15; ~i; i--) {
			int tmp_y = nxt_y + (1 << i) * sign - sign;
			if (tmp_y < 1 || tmp_y > m) continue;
			if ((sign == 1 ? v[nxt_y][i] : v[tmp_y][i]) > h[x][0]) continue;
			nxt_y = tmp_y + sign;
		}
		if (nxt_y < 1 || nxt_y > m) return ans = abs(nxt_y - sign - y);
		return ans = abs(nxt_y - y) + max(dfs(x, nxt_y, 1), dfs(x, nxt_y, 3));
	}
}

int main() {
	ios_base::sync_with_stdio(0);
	cin.tie(0);
	int q;
	cin >> n >> m >> q;
	for (int i = 1; i <= n; i++) cin >> h[i][0];
	for (int i = 1; i <= m; i++) cin >> v[i][0];
	for (int j = 1; j < 16; j++) {
		for (int i = 1; i <= n - (1 << j) + 1; i++) {
			h[i][j] = max(h[i][j - 1], h[i + (1 << j - 1)][j - 1]);
		}
		for (int i = 1; i <= m - (1 << j) + 1; i++) {
			v[i][j] = max(v[i][j - 1], v[i + (1 << j - 1)][j - 1]);
		}
	}
	while (q--) {
		int x, y;
		cin >> x >> y;
		ll ans = 0;
		if (x < n) ans = max(ans, dfs(x + 1, y, 3) + 1);
		if (y < m) ans = max(ans, dfs(x, y + 1, 2) + 1);
		if (x > 1) ans = max(ans, dfs(x - 1, y, 1) + 1);
		if (y > 1) ans = max(ans, dfs(x, y - 1, 0) + 1);
		cout << ans << '\n';
	}
	return 0;
}

Compilation message (stderr)

abduction2.cpp: In function 'int main()':
abduction2.cpp:45:45: warning: suggest parentheses around '-' inside '<<' [-Wparentheses]
    h[i][j] = max(h[i][j - 1], h[i + (1 << j - 1)][j - 1]);
                                           ~~^~~
abduction2.cpp:48:45: warning: suggest parentheses around '-' inside '<<' [-Wparentheses]
    v[i][j] = max(v[i][j - 1], v[i + (1 << j - 1)][j - 1]);
                                           ~~^~~

• Subtask 1: 13 / 13
• Subtask 2: 10 / 10
• Subtask 3: 17 / 17
• Subtask 4: 4 / 4
• Subtask 5: 56 / 56