原题链接：https://www.luogu.org/problem/P5151
这题我一开始是从赛后总结里过来的，看到置换乘法啥的，吓死我了。然后瞄了一眼题解，原来倍增也能过，但是比较坑的是，他这个边界压的很恶心，2^31，多了不行，少了也不行，多了估计会int爆掉，少了会WA几个点。我提交了好几次才调整好这个边界，可能是我太菜了。
#include<bits/stdc++.h> using namespace std; inline long long read() { char ch = getchar(); long long x = 0;short f = 1; while(ch < ‘0‘ || ch > ‘9‘) { if(ch == ‘-‘) f = -1; ch = getchar(); } while(‘0‘ <= ch && ch <= ‘9‘) { x = x * 10 + ch - ‘0‘; ch = getchar(); } return x * f; } int f [1000001][33]; inline int query (int x,int k) { unsigned long long now = 0; for (int i = 31;i >= 0;-- i) { if (now + (1 << i) > k) { continue ; } now += 1 << i; x = f [x][i]; } return x; } int tong [1000005]; int main() { int n = read (),k = read (); for (int i = 1;i <= n;++ i) { f [i][0] = read (); } //开始倍增 for (int rk = 1;rk <= 32;++ rk) { for (int i = 1;i <= n;++ i) { f [i][rk] = f [f [i][rk - 1]][rk - 1]; } } //开始查询 for (int i = 1;i <= n;++ i) { int temp = query (i,k); tong [temp] = i; } for (int i = 1;i <= n;++ i) { cout << tong [i]; if (i != n) { cout << " "; } } return 0; }
原文：https://www.cnblogs.com/dorbmon/p/12353985.html