CF356A Knight Tournament

#include <bits/stdc++.h>
using namespace std;
const int maxn = 3e5 + 10;
int n,m,fa[maxn],col[maxn];
int find(int x){
    return fa[x] == x ? x : fa[x] = find(fa[x]);
}
void merge(int l,int r,int x){
    while(l <= r){
        if(find(l) == l){
            col[l] = x;
            //=x,运行超时
            fa[l] = l + 1;
        }
        l = fa[l];
    }
}
int main(){
    //freopen("in","r",stdin);
    ios::sync_with_stdio(0);
    cin >> n >> m;
    //如果要是n的话，内存超限
    for(int i = 1; i <= n + 1; i++)
        fa[i] = i;
    for(int i = 1; i <= m; i++){
        int l,r,x;
        cin >> l >> r >> x;
        merge(l, x - 1,x);
        merge(x + 1,r,x);
    }
    for(int i = 1; i <= n; i++){
        if(i == 1) cout << col[i];
        else cout << " " << col[i];
    }
    return 0;
}