oj.uz

답안 #136441

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
136441 2019-07-25T10:10:14 Z onjo0127 Link (CEOI06_link) C++11
100 / 100
 552 ms 51880 KB 
#include <bits/stdc++.h>
using namespace std;
#define sz(V) ((int)V.size())

const int _N = 500009, DBG = 0;
bool chk[_N];
int N, K, A[_N], vs[_N], dep[_N], rt[_N], rid[_N], ith[_N], p[_N], cs[_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();

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

		st.insert(1e9);

		int mn = 1e9, stt = *st.begin();
		for(int j=stt-K; j<=stt; j++) {
			int jt = (j+M) % M;
			if(*st.lower_bound(jt) != jt) continue;
			int sum = 0, cnt = 0, now = jt;
			while(sum < M) {
				sum += cs[now];
				++cnt;
				now = p[now];
			}
			mn = min(mn, cnt);
		}
		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);
             ~~~~~^~~~~~~~~~~~~~

Subtask #1
100.0 / 100.0

# 결과 실행 시간 메모리 Grader output
1 Correct 13 ms 12152 KB Output is correct
2 Correct 12 ms 12152 KB Output is correct
3 Correct 13 ms 12152 KB Output is correct
4 Correct 13 ms 12280 KB Output is correct
5 Correct 15 ms 12456 KB Output is correct
6 Correct 30 ms 14328 KB Output is correct
7 Correct 42 ms 15348 KB Output is correct
8 Correct 56 ms 17140 KB Output is correct
9 Correct 103 ms 21428 KB Output is correct
10 Correct 84 ms 20928 KB Output is correct
11 Correct 148 ms 36968 KB Output is correct
12 Correct 164 ms 23404 KB Output is correct
13 Correct 223 ms 31752 KB Output is correct
14 Correct 276 ms 36136 KB Output is correct
15 Correct 341 ms 38960 KB Output is correct
16 Correct 404 ms 48500 KB Output is correct
17 Correct 454 ms 43592 KB Output is correct
18 Correct 532 ms 46152 KB Output is correct
19 Correct 526 ms 45860 KB Output is correct
20 Correct 461 ms 43712 KB Output is correct
21 Correct 497 ms 47260 KB Output is correct
22 Correct 524 ms 49172 KB Output is correct
23 Correct 552 ms 51880 KB Output is correct
24 Correct 477 ms 49092 KB Output is correct
25 Correct 468 ms 48364 KB Output is correct