[JSOI2008]最大数
这道题是板子题，用来练习线段树。
1 #include <bits/stdc++.h> 2 3 using namespace std; 4 5 #define re register 6 #define rep(i, a, b) for (re int i = a; i <= b; ++i) 7 #define repd(i, a, b) for (re int i = a; i >= b; --i) 8 #define maxx(a, b) a = max(a, b); 9 #define minn(a, b) a = min(a, b); 10 #define LL long long 11 #define inf (1 << 30) 12 13 const int maxn = 2e5 + 5, N = 2e5; 14 15 struct Seg_T { 16 #define lson (o << 1) 17 #define rson (o << 1 | 1) 18 int v[maxn << 4]; 19 void pushup(int o) { v[o] = max(v[lson], v[rson]); } 20 void add(int o, int l, int r, int x, int t) { 21 if (l == r) { v[o] = t; return; } 22 int mid = (l + r) >> 1; 23 if (x <= mid) add(lson, l, mid, x, t); 24 else add(rson, mid+1, r, x, t); 25 pushup(o); 26 } 27 int query(int o, int l, int r, int ql, int qr) { 28 if (ql <= l && r <= qr) return v[o]; 29 int mid = (l + r) >> 1, ans = 0; 30 if (ql <= mid) ans = max(ans, query(lson, l, mid, ql, qr)); 31 if (mid < qr) ans = max(ans, query(rson, mid+1, r, ql, qr)); 32 return ans; 33 } 34 } S; 35 36 int n, L = 0; 37 LL D, t; 38 39 int main() { 40 scanf("%d %lld", &n, &D); 41 42 rep(i, 1, n) { 43 char c[2]; LL x; 44 scanf("%s %lld", c, &x); 45 if (c[0] == 'Q') printf("%lld\n", t = S.query(1, 1, N, L-x+1, L)); 46 else { 47 L++; 48 S.add(1, 1, N, L, (t+x) % D); 49 } 50 } 51 52 return 0; 53 }
