HDU 1754 line segment tree

[Cpp] <span style = "font-size: 32px; "> # include <iostream> # include <string> # include <cstring> # include <algorithm> # include <cstdio> # include <cmath> # include <cctype> # include <iomanip> # define Lson left, t, rt <1 # define Rson t + 1, right, rt <1 | 1 using namespace std; const int maxn = 200005; int f [maxn <2]; void PushUP (int rt) {f [rt] = max (f [rt <1], f [rt <1 | 1]);} void build (int left, int right, int rt) {if (left = right) {cin> f [rt]; return;} int t = (left + right)> 1; build (Lson); build (Rson); PushUP (rt);} void update (int ii, int value, int left, int right, int rt) {if (left = right) {f [rt] = value; return;} int t = (left + right)> 1; if (ii <= t) update (ii, value, Lson); else update (ii, value, Rson); PushUP (rt);} int query (int l, int r, int left, int right, int rt) {if (l <= left & r> = right) return f [rt]; int t = (left + right)/2; int ret = 0; if (l <= t) ret = max (ret, query (l, r, Lson); if (r> t) ret = max (ret, query (l, r, Rson); return ret;} int main () {int n, m; while (cin >>n> m) {build (1, n, 1 ); while (m --) {char C; int a, B; // for (int I = 0; I <= n; ++ I) cout <f [I] <''; cout <endl; cin> C> a> B; if (C = 'q ') cout <query (a, B, 1, n, 1) <endl; else update (a, B, 1, n, 1) ;}} return 0 ;} </span>