Submission #136301

# Submission time Handle Problem Language Result Execution time Memory
136301 2019-07-25T06:00:42 Z 이온조(#3259) Link (CEOI06_link) C++14
100 / 100
615 ms 62068 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[22][_N], cs[22][_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[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:120:43: warning: 'L' may be used uninitialized in this function [-Wmaybe-uninitialized]
     sum += cs[j][now], cnt += (1<<j), now = p[j][now];
                                       ~~~~^~~~~~~~~~~
# Verdict Execution time Memory Grader output
1 Correct 13 ms 12152 KB Output is correct
2 Correct 12 ms 12280 KB Output is correct
3 Correct 13 ms 12280 KB Output is correct
4 Correct 14 ms 12404 KB Output is correct
5 Correct 15 ms 12536 KB Output is correct
6 Correct 34 ms 14972 KB Output is correct
7 Correct 44 ms 15988 KB Output is correct
8 Correct 60 ms 18280 KB Output is correct
9 Correct 93 ms 24904 KB Output is correct
10 Correct 112 ms 23748 KB Output is correct
11 Correct 168 ms 53356 KB Output is correct
12 Correct 210 ms 23936 KB Output is correct
13 Correct 242 ms 37712 KB Output is correct
14 Correct 290 ms 42272 KB Output is correct
15 Correct 387 ms 49140 KB Output is correct
16 Correct 419 ms 61128 KB Output is correct
17 Correct 469 ms 53836 KB Output is correct
18 Correct 556 ms 52032 KB Output is correct
19 Correct 541 ms 52784 KB Output is correct
20 Correct 545 ms 50908 KB Output is correct
21 Correct 554 ms 57544 KB Output is correct
22 Correct 615 ms 59400 KB Output is correct
23 Correct 584 ms 62068 KB Output is correct
24 Correct 541 ms 59276 KB Output is correct
25 Correct 537 ms 58412 KB Output is correct