oj.uz

답안 #136426

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
136426 2019-07-25T09:46:04 Z onjo0127 Link (CEOI06_link) C++11
100 / 100
 641 ms 61056 KB 
#include <bits/stdc++.h>
using namespace std;
#define sz(V) ((int)V.size())

const int _N = 500001, DBG = 0;
bool chk[_N];
int N, K, A[_N], vs[_N], dep[_N], rt[_N], rid[_N], ith[_N], p[15][_N], cs[15][_N], ans;
vector<vector<int> > R;
vector<int> S, G[_N];

void go(int x, int col) {
	S.push_back(x);
	vs[x] = col;
	if(vs[A[x]]) {
		if(vs[A[x]] == col) {
			vector<int> T;
			while(1) {
				int tmp = S.back(); S.pop_back();
				T.push_back(tmp);
				if(tmp == A[x]) break;
			}
			reverse(T.begin(), T.end());
			for(int i=0; i<T.size(); i++) rid[T[i]] = sz(R), ith[T[i]] = i+1;
			R.push_back(T);
		}
	}
	else go(A[x], col);
}

int mrk(int x, int k) {
	if(k <= 0) return x;
	chk[x] = 1;
	int d;
	if(ith[x]) {
		if(ith[x] < ith[A[x]]) d = ith[A[x]] - ith[x];
		else d = ith[A[x]] - ith[x] + sz(R[rid[x]]);
	}
	else if(ith[A[x]]) return A[x] = mrk(rt[x], k - dep[x]);
	else d = dep[x] - dep[A[x]];
	return A[x] = mrk(A[x], k - d);
}

void dfs(int RT, int x, int d) {
	// printf("dfs: x: %d, d: %d\n", x, d);
	dep[x] = d; rt[x] = RT;
	for(auto& it: G[x]) dfs(RT, it, d+1);
}

void showstat() {
	puts("Showing...");
	printf("answer: %d\n", ans);
	for(int i=1; i<=N; i++) printf("%d", chk[i]);
	puts("\n---------------------");
}

int main() {
	vector<int> Q;
	scanf("%d%d",&N,&K);
	for(int i=1; i<=N; i++) {
		int a, b; scanf("%d%d",&a,&b);
		A[a] = b;
	}
	for(int i=1; i<=N; i++) if(!vs[i]) go(i, i);
	for(int i=1; i<=N; i++) if(!ith[i]) {
		G[A[i]].push_back(i);
		Q.push_back(i);
	}
	for(int i=1; i<=N; i++) if(ith[i]) dfs(i, i, 0);
	chk[1] = 1;
	mrk(A[1], K);
	if(DBG) showstat();
	sort(Q.begin(), Q.end(), [&](int PP, int QQ) { return dep[PP] > dep[QQ]; });
	for(auto& it: Q) {
		if(chk[it]) continue;
		mrk(it, K); ++ans;
	}
	if(DBG) showstat();

	set<int> st;
	for(auto& it: R) {
		st.clear();
		int M = sz(it);
		for(int j=0; j<M; j++) {
			p[0][j] = j; cs[0][j] = 0;
			if(!chk[it[j]]) st.insert(j);
		}
		if(st.empty()) continue;

		for(auto& jt: st) {
			if(jt <= M-K) {
				auto kt = st.lower_bound(jt + K);
				if(kt == st.end()) {
					p[0][jt] = *st.begin();
					cs[0][jt] = *st.begin() - jt + M;
				}
				else {
					p[0][jt] = *kt;
					cs[0][jt] = *kt - jt;
				}
			}
			else {
				auto kt = st.lower_bound(jt + K - M);
				if(kt == st.end()) p[0][jt] = jt, cs[0][jt] = M;
				else p[0][jt] = *kt, cs[0][jt] = *kt - jt + M;
			}
			// printf("next[%d]: %d, cost: %d\n", jt, p[0][jt], cs[0][jt]);
		}

		int L;
		for(int i=1; (1<<i)<=M; i++) {
			for(int j=0; j<M; j++) {
				p[i][j] = p[i-1][p[i-1][j]];
				cs[i][j] = cs[i-1][j] + cs[i-1][p[i-1][j]];
				cs[i][j] = min(cs[i][j], M);
			}
			L = i;
		}
		int mn = 1e9;
		for(auto& jt: st) {
			int sum = 0, now = jt, cnt = 0;
			for(int j=L; j>=0; j--) if(sum + cs[j][now] < M) {
				sum += cs[j][now], cnt += (1<<j), now = p[j][now];
				// printf("now: %d, sum: %d, cnt: %d\n", now, sum, cnt);
			}
			mn = min(mn, cnt + 1);
			// printf("jt: %d, cnt: %d\n", jt, cnt + 1);
		}
		ans += mn;
	}
	printf("%d", ans);
	return 0;
}

Compilation message

link.cpp: In function 'void go(int, int)':
link.cpp:23:18: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
    for(int i=0; i<T.size(); i++) rid[T[i]] = sz(R), ith[T[i]] = i+1;
                 ~^~~~~~~~~
link.cpp: In function 'int main()':
link.cpp:58:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d%d",&N,&K);
  ~~~~~^~~~~~~~~~~~~~
link.cpp:60:18: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   int a, b; scanf("%d%d",&a,&b);
             ~~~~~^~~~~~~~~~~~~~
link.cpp:122:43: warning: 'L' may be used uninitialized in this function [-Wmaybe-uninitialized]
     sum += cs[j][now], cnt += (1<<j), now = p[j][now];
                                       ~~~~^~~~~~~~~~~

Subtask #1
100.0 / 100.0

# 결과 실행 시간 메모리 Grader output
1 Correct 13 ms 12152 KB Output is correct
2 Correct 13 ms 12280 KB Output is correct
3 Correct 13 ms 12280 KB Output is correct
4 Correct 14 ms 12408 KB Output is correct
5 Correct 15 ms 12536 KB Output is correct
6 Correct 31 ms 14968 KB Output is correct
7 Correct 44 ms 15984 KB Output is correct
8 Correct 72 ms 18264 KB Output is correct
9 Correct 100 ms 24980 KB Output is correct
10 Correct 90 ms 23696 KB Output is correct
11 Correct 168 ms 51424 KB Output is correct
12 Correct 175 ms 24080 KB Output is correct
13 Correct 237 ms 37328 KB Output is correct
14 Correct 365 ms 41852 KB Output is correct
15 Correct 357 ms 47888 KB Output is correct
16 Correct 454 ms 59464 KB Output is correct
17 Correct 448 ms 52592 KB Output is correct
18 Correct 553 ms 51752 KB Output is correct
19 Correct 520 ms 52380 KB Output is correct
20 Correct 519 ms 50576 KB Output is correct
21 Correct 517 ms 56280 KB Output is correct
22 Correct 524 ms 58116 KB Output is correct
23 Correct 633 ms 61056 KB Output is correct
24 Correct 506 ms 58020 KB Output is correct
25 Correct 641 ms 57364 KB Output is correct