Submission #765163

#	Time	Username	Problem	Language	Result	Execution time	Memory
765163		Sohsoh84	Wombats (IOI13_wombats)	C++17	55 / 100	20028 ms	204096 KiB

wombats

#include "wombats.h"
#include <bits/stdc++.h>

using namespace std;

typedef long long ll;
typedef pair<int, int> pll;

#define X		first
#define Y		second
#define sep		' '
#define debug(x)	cerr << #x << ": " << x << endl;

const ll MAXN = 5000 + 10;
const ll MAXM = 200 + 10;
const ll INF = 1e9 + 10;
const ll LIM = 10;

int n, m, H[MAXN][MAXM], V[MAXN][MAXM], ps[MAXN][MAXM], sg[MAXN / LIM * 2 + 5][MAXM][MAXM], opt[MAXM][MAXM], 
    lc[MAXN << 1], rc[MAXN << 1], sgsz = 1, dist[MAXN][MAXM];

inline void update_ps(int i) {
	for (int j = 2; j <= m; j++)
		ps[i][j] = ps[i][j - 1] + H[i][j - 1];
}

inline void update_ans(int mid, int v) { // opt[i - 1][j] <= opt[i][j] <= opt[i][j + 1]
	for (int i = 1; i <= m; i++) {
		opt[i][m + 1] = m;
		opt[0][i] = 1;
	}

	for (int i = 1; i <= m; i++) {
		for (int j = m; j > 0; j--) {
			int optl = opt[i - 1][j], optr = opt[i][j + 1];
			sg[v][i][j] = INF;
			opt[i][j] = optl;

			for (int t = optl; t <= optr; t++) {
				int cost = sg[lc[v]][i][t] + V[mid][t] + sg[rc[v]][t][j];
				if (cost < sg[v][i][j]) {
					sg[v][i][j] = cost;
					opt[i][j] = t;
				}
			}
		}
	}
}

inline void dijkstra(int x, int y, int r) {
	priority_queue<pair<ll, pll>, vector<pair<ll, pll>>, greater<pair<ll, pll>>> pq;
	for (int i = x; i <= r; i++)
		for (int j = 1; j <= m; j++)
			dist[i][j] = INF;

	dist[x][y] = 0;
	pq.push({dist[x][y], {x, y}});
	
	while (!pq.empty()) {
		auto [d, pos] = pq.top();
		pq.pop();
		auto [x, y] = pos;
		if (dist[x][y] != d) continue;

		if (x < r && dist[x + 1][y] > dist[x][y] + V[x][y]) {
			dist[x + 1][y] = dist[x][y] + V[x][y];
			pq.push({dist[x + 1][y], {x + 1, y}});
		}

		if (y > 1 && dist[x][y - 1] > dist[x][y] + H[x][y - 1]) {
			dist[x][y - 1] = dist[x][y] + H[x][y - 1];
			pq.push({dist[x][y - 1], {x, y - 1}});
		}

		if (y < m && dist[x][y + 1] > dist[x][y] + H[x][y]) {
			dist[x][y + 1] = dist[x][y] + H[x][y];
			pq.push({dist[x][y + 1], {x, y + 1}});
		}
	}
}

inline void tof(int l, int r, int v) {
	for (int i = 1; i <= m; i++) {
		dijkstra(l, i, r);
		for (int j = 1; j <= m; j++)
			sg[v][i][j] = dist[r][j];
	}
}

void build(int l = 1, int r = n, int v = 1) {
	if (r - l + 1 <= LIM) {
		tof(l, r, v);
	} else {
		int mid = (l + r) >> 1;
		lc[v] = ++sgsz;
		rc[v] = ++sgsz;
		build(l, mid, lc[v]);
		build(mid + 1, r, rc[v]);
		update_ans(mid, v);
	}
}

void update(int ind, int l = 1, int r = n, int v = 1) {
	if (r - l + 1 <= LIM) {
		tof(l, r, v);
	} else {
		int mid = (l + r) >> 1;
		if (ind <= mid) update(ind, l, mid, lc[v]);
		else update(ind, mid + 1, r, rc[v]);
		
		update_ans(mid, v);
	}
}

void init(int R_, int C_, int H_[5000][200], int V_[5000][200]) {
	n = R_, m = C_;
	for (int i = 1; i <= n; i++)
		for (int j = 1; j < m; j++)
			H[i][j] = H_[i - 1][j - 1];
	
	for (int i = 1; i < n; i++)
		for (int j = 1; j <= m; j++)
			V[i][j] = V_[i - 1][j - 1];

	for (int i = 1; i <= n; i++)
		update_ps(i);
	
	build();
}

void changeH(int P, int Q, int W) {
	P++, Q++;
	H[P][Q] = W;
	update_ps(P);
	update(P);
}

void changeV(int P, int Q, int W) {
	P++, Q++;
	V[P][Q] = W;
	update(P);
}

int escape(int V1, int V2) {
	V1++, V2++;
	return sg[1][V1][V2];
}

// TODO: 1-base
// TODO: check fit in ll
// TODO: change max limits
// TODO: check n == 1
// TODO: check bounds(n / m)

Compilation message (stderr)

grader.c: In function 'int main()':
grader.c:15:6: warning: variable 'res' set but not used [-Wunused-but-set-variable]
   15 |  int res;
      |      ^~~

• Subtask 1: 9 / 9
• Subtask 2: 12 / 12
• Subtask 3: 16 / 16
• Subtask 4: 18 / 18
• Subtask 5: 0 / 21
• Subtask 6: 0 / 24