답안 #24469

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
24469 2017-06-09T09:46:33 Z Bruteforceman Tug of War (BOI15_tug) C++11
0 / 100
46 ms 5496 KB
#include "bits/stdc++.h"
using namespace std;
bool del[2 * 30005];
int deg[2][30005];
vector <int> g[2][30005];

struct data
{
	int l, r, s;
	data () {}
	data (int l, int r, int s) : l(l), r(r), s(s) {}
} a[2 * 30005];

struct node
{
	int i, side;
	node () {}
	node (int i, int side) : i(i), side(side) {}
};

bool play[2 * 30010];
bool vis[2][30010];
int sum;
bool pl[2 * 30010];
bool vs[2][30010];

int len;


void cycle(node n) {
	// cout << n.i << " " << n.side << endl;
	++len;
	if(n.side == -1) {
		play[n.i] = true;
		if(vis[0][a[n.i].l] == false) {
			cycle(node(a[n.i].l, 0));
			sum += a[n.i].s;
		} else {
			cycle(node(a[n.i].r, 1));
			sum -= a[n.i].s;
		}
	} else {
		vis[n.side][n.i] = true;
		for(auto i : g[n.side][n.i]) {
			if(del[i] == false && play[i] == false) {
				cycle(node(i, -1));
				break;
			}
		}
	}
}

void loop(node n) {
	if(n.side == -1) {
		pl[n.i] = true;
		if(vs[1][a[n.i].r] == false) {
			loop(node(a[n.i].r, 1));
			sum -= a[n.i].s;
		} else {
			loop(node(a[n.i].l, 0));
			sum += a[n.i].s;
		}
	} else {
		vs[n.side][n.i] = true;
		for(auto i : g[n.side][n.i]) {
			if(del[i] == false && pl[i] == false) {
				loop(node(i, -1));
				break;
			}
		}
	}
}

const int tot = 40 * 2005;
bitset <tot> dp;

void knapsack(vector <int> v) {
	dp[0] = 1;
	for(auto i : v) {
		dp |= dp << i;
	}
}

int main(int argc, char const *argv[])
{
	int n, k;
	scanf("%d %d", &n, &k);
	for(int i = 1; i <= n+n; i++) {
		int l, r, s;
		scanf("%d %d %d", &l, &r, &s);
		a[i] = data(l, r, s);
		g[0][l].push_back(i);
		g[1][r].push_back(i);
		++deg[0][l];
		++deg[1][r];
	}
	queue <node> Q;
	for(int i = 1; i <= n; i++) {
		if(deg[0][i] == 1) Q.push(node(i, 0));
		if(deg[1][i] == 1) Q.push(node(i, 1));
		
		if(deg[0][i] == 0 || deg[1][i] == 0) {
			printf("NO\n");
			exit(0);
		}
	}
	int add[2];
	add[0] = add[1] = 0;
	while(!Q.empty()) {
		node p = Q.front();
		Q.pop();
		for(auto i : g[p.side][p.i]) {
			if(del[i] == false) {
				add[p.side] += a[i].s;
				del[i] = true;
				if(p.side == 0) {
					--deg[1][a[i].r];
					if(deg[1][a[i].r] == 1) {
						Q.push(node(a[i].r, 1));
					}
					if(deg[1][a[i].r] == 0) {
						printf("NO\n");
						exit(0);
					}
				} else {
					--deg[0][a[i].l];
					if(deg[0][a[i].l] == 1) {
						Q.push(node(a[i].l, 0));
					}
					if(deg[0][a[i].l] == 0) {
						printf("NO\n");
						exit(0);
					}
				}
			}
		}
	}
	vector <int> v;
	int neg = 0;
	for(int i = 1; i <= n+n; i++) {
		if(play[i] == false) {
			int k1, k2;

			len = 0;

			sum = 0;
			cycle(node(i, -1));
			k1 = sum;

			assert(len % 4 == 0);

			sum = 0;
			loop(node(i, -1));
			k2 = sum;
			if(k1 < k2) swap(k1, k2);

			v.push_back(k1 - k2);
			neg += k2;
		}
	} 

	knapsack(v);
	add[0] -= add[1];
	for(int i = 0; i < tot; i++) {
		if(dp[i] == 1) {
			int hehe = i + neg + add[0];
			if(abs(hehe) <= k) {
				printf("YES\n");
				exit(0);
			}
		}
	}
 	printf("NO\n");
	return 0; 
}

Compilation message

tug.cpp: In function 'int main(int, const char**)':
tug.cpp:87:24: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d %d", &n, &k);
                        ^
tug.cpp:90:32: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   scanf("%d %d %d", &l, &r, &s);
                                ^
# 결과 실행 시간 메모리 Grader output
1 Correct 0 ms 4668 KB Output is correct
2 Correct 0 ms 4668 KB Output is correct
3 Correct 0 ms 4668 KB Output is correct
4 Correct 0 ms 4668 KB Output is correct
5 Correct 0 ms 4668 KB Output is correct
6 Correct 0 ms 4668 KB Output is correct
7 Correct 0 ms 4668 KB Output is correct
8 Correct 0 ms 4668 KB Output is correct
9 Correct 0 ms 4668 KB Output is correct
10 Correct 0 ms 4668 KB Output is correct
11 Correct 0 ms 4668 KB Output is correct
12 Correct 0 ms 4668 KB Output is correct
13 Correct 0 ms 4668 KB Output is correct
14 Correct 0 ms 4668 KB Output is correct
15 Correct 0 ms 4668 KB Output is correct
16 Correct 0 ms 4668 KB Output is correct
17 Correct 0 ms 4668 KB Output is correct
18 Correct 0 ms 4668 KB Output is correct
19 Correct 0 ms 4668 KB Output is correct
20 Correct 0 ms 4668 KB Output is correct
21 Correct 0 ms 4668 KB Output is correct
22 Runtime error 0 ms 4672 KB Execution killed because of forbidden syscall gettid (186)
23 Halted 0 ms 0 KB -
# 결과 실행 시간 메모리 Grader output
1 Correct 0 ms 4668 KB Output is correct
2 Correct 0 ms 4668 KB Output is correct
3 Correct 0 ms 4668 KB Output is correct
4 Correct 0 ms 4668 KB Output is correct
5 Correct 0 ms 4668 KB Output is correct
6 Correct 0 ms 4668 KB Output is correct
7 Correct 0 ms 4668 KB Output is correct
8 Correct 0 ms 4668 KB Output is correct
9 Correct 0 ms 4668 KB Output is correct
10 Correct 0 ms 4668 KB Output is correct
11 Correct 0 ms 4668 KB Output is correct
12 Correct 0 ms 4668 KB Output is correct
13 Correct 0 ms 4668 KB Output is correct
14 Correct 0 ms 4668 KB Output is correct
15 Correct 0 ms 4668 KB Output is correct
16 Correct 0 ms 4668 KB Output is correct
17 Correct 0 ms 4668 KB Output is correct
18 Correct 0 ms 4668 KB Output is correct
19 Correct 0 ms 4668 KB Output is correct
20 Correct 0 ms 4668 KB Output is correct
21 Correct 0 ms 4668 KB Output is correct
22 Runtime error 0 ms 4672 KB Execution killed because of forbidden syscall gettid (186)
23 Halted 0 ms 0 KB -
# 결과 실행 시간 메모리 Grader output
1 Correct 16 ms 5496 KB Output is correct
2 Correct 9 ms 5328 KB Output is correct
3 Correct 23 ms 5496 KB Output is correct
4 Correct 9 ms 5328 KB Output is correct
5 Correct 16 ms 5496 KB Output is correct
6 Correct 0 ms 5328 KB Output is correct
7 Correct 43 ms 5496 KB Output is correct
8 Correct 9 ms 5328 KB Output is correct
9 Correct 16 ms 5496 KB Output is correct
10 Correct 9 ms 5328 KB Output is correct
11 Correct 19 ms 5496 KB Output is correct
12 Correct 3 ms 5328 KB Output is correct
13 Correct 19 ms 5496 KB Output is correct
14 Correct 36 ms 5496 KB Output is correct
15 Correct 6 ms 5328 KB Output is correct
16 Correct 46 ms 5496 KB Output is correct
17 Correct 16 ms 5328 KB Output is correct
18 Correct 36 ms 5496 KB Output is correct
19 Correct 6 ms 5328 KB Output is correct
20 Correct 29 ms 5496 KB Output is correct
21 Correct 13 ms 5196 KB Output is correct
22 Runtime error 13 ms 5332 KB Execution killed because of forbidden syscall gettid (186)
# 결과 실행 시간 메모리 Grader output
1 Correct 0 ms 4668 KB Output is correct
2 Correct 0 ms 4668 KB Output is correct
3 Correct 0 ms 4668 KB Output is correct
4 Correct 0 ms 4668 KB Output is correct
5 Correct 0 ms 4668 KB Output is correct
6 Correct 0 ms 4668 KB Output is correct
7 Correct 0 ms 4668 KB Output is correct
8 Correct 0 ms 4668 KB Output is correct
9 Correct 0 ms 4668 KB Output is correct
10 Correct 0 ms 4668 KB Output is correct
11 Correct 0 ms 4668 KB Output is correct
12 Correct 0 ms 4668 KB Output is correct
13 Correct 0 ms 4668 KB Output is correct
14 Correct 0 ms 4668 KB Output is correct
15 Correct 0 ms 4668 KB Output is correct
16 Correct 0 ms 4668 KB Output is correct
17 Correct 0 ms 4668 KB Output is correct
18 Correct 0 ms 4668 KB Output is correct
19 Correct 0 ms 4668 KB Output is correct
20 Correct 0 ms 4668 KB Output is correct
21 Correct 0 ms 4668 KB Output is correct
22 Runtime error 0 ms 4672 KB Execution killed because of forbidden syscall gettid (186)
23 Halted 0 ms 0 KB -