如题

这个代码 AC 了

#include<cstdio>
#include<iostream>
#include<algorithm>
#include<stack>
#include<vector>
#include<queue>
#include<cstring>
#include<cmath>
#include<set>
using namespace std;
int fa[1000005];
int val[1000005];
int lc[1000005];
int rc[1000005];
int dis[1000005];
int merge(int x, int y){
    if(x == 0 || y == 0){
        return x + y;
	}
	if(val[x] > val[y] || (val[x] == val[y] && x > y)){
	    swap(x, y);
	}
	rc[x] = merge(rc[x], y);
	fa[rc[x]] = x;
	if(dis[lc[x]] < lc[rc[x]]){
	    swap(lc[x], rc[x]);
	}
	dis[x] = dis[rc[x]] + 1;
	return x;
}
void pop(int x){
    val[x] = -1;
    fa[lc[x]] = lc[x];
    fa[rc[x]] = rc[x];
    fa[x] = merge(lc[x], rc[x]);
}
int find(int x){
    if(fa[x] == x){
        return x;
	}
	fa[x] = find(fa[x]);
	return fa[x];
}
int main(){
    int n, m;
    cin >> n >> m;
    for(int i = 1; i <= n; i++){
        cin >> val[i];
        fa[i] = i;
	}
	dis[0] = -1;
	for(int i = 0; i < m; i++){
	    int t, u, v;
	    cin >> t;
	    if(t == 1){
	    	cin >> u >> v;
	        if(val[u] == -1 || val[v] == -1){
	            continue;
			}
			int uu = find(u);
			int vv = find(v);
			fa[uu] = fa[vv] = merge(uu, vv);
		} else {
		    cin >> u;
		    if(val[u] == -1){
		        cout << -1 << endl;
			} else {
				int t = find(u);
				cout << val[t] << endl;
			    pop(t);  
		    }
		}
	}
    return 0;
}

里

int merge(int x, int y){
    if(x == 0 || y == 0){
        return x + y;
	}
	if(val[x] > val[y] || (val[x] == val[y] && x > y)){
	    swap(x, y);
	}
	rc[x] = merge(rc[x], y);
	fa[rc[x]] = x;
	if(dis[lc[x]] < lc[rc[x]]){
	    swap(lc[x], rc[x]);
	}
	dis[x] = dis[rc[x]] + 1;
	return x;
}

里

if(dis[lc[x]] < lc[rc[x]]){
	    swap(lc[x], rc[x]);
	}

$lc[rc[x]]$