segment tree
https://www.acmicpc.net/problem/10167 http://www.spoj.com/problems/KQUERY/ http://codeforces.com/contest/380/problem/C -- 정보 http://codeforces.com/blog/entry/15890 http://codeforces.com/blog/entry/15729 struct SegmentTree { int n; vector<int> s; SegmentTree ():n(N),s(N<<2,INT_MAX){} void build (int id=1, int l=0, int r=N-1) { if(r==l){ s[id] = INT_MAX // or a[l]; return; } int mid = (l+r)>>1; build(id<<1, l, mid); build(id<<1|1, mid+1, r); s[id] = min(s[id<<1] , s[id<<1|1]); } void modify (int p, int x, int id=1, int l=0, int r=N-1) { s[id] = min(s[id], x); if(r==l)return; int mid = (l+r)>>1; if(p <= mid) modify(p, x, id<<1, l, mid); else modify(p, x, id<<1|1, mid+1, r); } int query (int x, int y, int id=1, int l=0, int