【BZOJ2054】疯狂的馒头（并查集）

/*
经典思路， 倒序并查集处理即可


*/

#include<cstdio>
#include<algorithm>
#include<cstring>
#include<queue>
#include<iostream>
#define ll long long
#define mmp make_pair
#define M 1000010
using namespace std;
int read() {
	int nm = 0, f = 1;
	char c = getchar();
	for(; !isdigit(c); c = getchar()) if(c == '-') f = -1;
	for(; isdigit(c); c = getchar()) nm = nm * 10 + c - '0';
	return nm * f;
}
int father[M], cor[M], n, m, p, q;

int find(int x) {
	return father[x] == x ? x : father[x] = find(father[x]);
}

int main() {
	n = read(), m = read(), p = read(), q = read();
	for(int i = 1; i <= n + 1; i++) father[i] = i;
	for(int i = m; i >= 1; i--) {
		int l = (1ll * p * i + q) % n + 1, r = (1ll * i * q + p) % n + 1;
		if(l > r) swap(l, r);
		for(int j = find(l); j <= r; j = find(j + 1)) cor[j] = i, father[j] = find(j + 1);
	}
	for(int i = 1; i <= n; i++) cout << cor[i] << "
";
	
	return 0;
}