左偏树 hdu1512

#include <iostream>#include <cstdio>#include <algorithm>#include <cstring>#include <cmath>#include <string>#define Rep(i, x, y) for (int i = x; i <= y; i ++)#define RepE(i, x) for (int i = pos[x]; i; i = g[i].nex)#define Dwn(i, x, y) for (int i = x; i >= y; i --)#define u t[x]#define r t[y]#define lc u.ch[0]#define rc u.ch[1]#define Rc t[rc]#define Lc t[lc]using namespace std;typedef long long LL;const int N = 100005;struct arr { int ch[2], vl, d; } t[N];int n, par[N], a[N], m;int Fd(int x) { return (par[x] == x) ? x : (par[x] = Fd(par[x])); }int Merge(int x, int y) {    if (!x || !y) return max(x, y);    if (u.vl < r.vl) swap(x, y);    rc = Merge(rc, y);    par[rc] = x;    if (Rc.d > Lc.d) swap(rc, lc);    (!rc) ? u.d = 0 : u.d = Rc.d + 1;    return x;}int Del(int x) {    par[lc] = lc, par[rc] = rc;    int y = Merge(lc, rc);    u.d = lc = rc = 0;    return y;}void Solve(int x, int y) {    int l1, r1;    u.vl /= 2, r.vl /= 2;    l1 = Del(x), r1 = Del(y);    l1 = Merge(l1, x);    r1 = Merge(r1, y);    x = Merge(l1, r1);    printf("%d\n", u.vl);}int main(){while (~scanf ("%d", &n)) {    Rep(x, 1, n) scanf ("%d", &a[x]), u.vl = a[x], par[x] = x, lc = rc = u.d = 0;    scanf ("%d", &m);    int x, y;    Rep(i, 1, m) {        scanf ("%d%d", &x, &y);        x = Fd(x), y = Fd(y);        if (x == y) { puts("-1"); continue ; }        Solve(x, y);    }}    return 0;}