BZOJ2054 疯狂的馒头 并查集

题意：懒得写了有空再补上

链接：http://www.lydsy.com/JudgeOnline/problem.php?id=2054

离线从后往前做，并查集维护下一个没染色的就可以啦～

#include<bits/stdc++.h>

using namespace std;

const int MAXN = 1010000;
long long n, m, p, q;
int fa[MAXN], color[MAXN];

template <typename tn> void read (tn & a) {
    tn x = 0, f = 1; char c = getchar();
    while (c < '0' || c > '9') { if (c == '-') f = -1; c = getchar(); }
    while (c >= '0' && c <= '9') { x = x * 10 + c - '0'; c = getchar(); }
    a = f == 1 ? x : -x;
}

int find (int x) { return (fa[x] == x || fa[x] == 0) ? x : fa[x] = find(fa[x]); }

int main() {
    read(n);
    read(m);
    read(p);
    read(q);
    for (int i = 1; i <= n; ++i) fa[i] = i;
    for (long long i = m; i > 0; --i) {
        long long x = (i * p + q) % n + 1, y = (i * q + p) % n + 1;
        if (x > y) { int t = x; x = y; y = t; }
        for (int j = find(x); j <= y; j = find(j)) color[j] = i, ++fa[j];
    }
    for (int i = 1; i <= n; ++i) printf("%d\n", color[i]);
    return 0;
}