标签:efi upd while ++ pen 更新 space ons txt
单点更新 区间查询
#include <bits/stdc++.h> using namespace std; #define m ((l+r)/2) #define ls (rt<<1) #define rs (rt<<1|1) const int N = 2e6+10; int s[N], tr[N]; void build(int rt,int l,int r) { if(l == r) { tr[rt] = s[l]; return ; } build(ls, l, m); build(rs, m+1, r); tr[rt] = min(tr[ls], tr[rs]); } void update(int rt,int l,int r,int pos,int val) { if(l == r && l == pos) { tr[rt] = val; return ; } if(pos <= m) update(ls, l, m, pos, val); else update(rs, m+1, r, pos, val); tr[rt] = min(tr[ls], tr[rs]); } int query(int rt,int l,int r,int L,int R) { if(L<=l && r<=R) { return tr[rt]; } int res = 0x3f3f3f3f; if(L <= m) res = min(res, query(ls,l,m,L,R)); if(R > m) res = min(res, query(rs,m+1,r,L,R)); return res; } void out(int rt,int l,int r) { printf("%d %d %d\n", l, r, tr[rt]); if(l == r ) { return ; } out(ls, l, m); out(rs, m+1, r); } int main() { freopen("in.txt","r",stdin); //freopen("out.txt","w",stdout); int n; scanf("%d", &n); for(int i=1; i<=n; i++) { scanf("%d", &s[i]); } build(1,1,n); // out(1,1,n); int t; scanf("%d", &t); while(t--) { int op,l,r; scanf("%d %d %d", &op, &l, &r); if(op) { update(1,1,n,l,r); //out(1,1,n); } else { printf("%d\n", query(1,1,n,l,r)); } // out(1,1,n); } return 0; }
hihoCoder week19 RMQ问题再临-线段树 单点更新 区间查询
标签:efi upd while ++ pen 更新 space ons txt
原文地址:https://www.cnblogs.com/Draymonder/p/10010356.html