diff --git a/Luogu/problem/P2880/P2880.cpp b/Luogu/problem/P2880/P2880.cpp new file mode 100644 index 00000000..b8de6684 --- /dev/null +++ b/Luogu/problem/P2880/P2880.cpp @@ -0,0 +1,72 @@ +#include + +using namespace std; + +struct node { + int l, r, max, min; + + node() { + l = r = max = 0; + min = 0x3f3f3f3f; + } + node(int _l, int _r) { + l = _l; + r = _r; + max = 0; + min = 0x3f3f3f3f; + } +} tr[50005 << 2]; +int n, q, a, b, h[50005]; + +void pushup(int u) { + tr[u].max = max(tr[u << 1].max, tr[u << 1 | 1].max); + tr[u].min = min(tr[u << 1].min, tr[u << 1 | 1].min); +} + +void build(int u, int l, int r) { + tr[u] = node(l, r); + if (l == r) { + tr[u].max = h[l]; + tr[u].min = h[l]; + return; + } + int mid = l + r >> 1; + build(u << 1, l, mid); + build(u << 1 | 1, mid + 1, r); + pushup(u); +} + +int query_max(int u, int l, int r) { + if (l <= tr[u].l && tr[u].r <= r) { + return tr[u].max; + } + int mid = tr[u].l + tr[u].r >> 1; + int s = 0; + if (l <= mid) s = max(s, query_max(u << 1, l, r)); + if (r > mid) s = max(s, query_max(u << 1 | 1, l, r)); + return s; +} + +int query_min(int u, int l, int r) { + if (l <= tr[u].l && tr[u].r <= r) { + return tr[u].min; + } + int mid = tr[u].l + tr[u].r >> 1; + int s = 0x3f3f3f3f; + if (l <= mid) s = min(s, query_min(u << 1, l, r)); + if (r > mid) s = min(s, query_min(u << 1 | 1, l, r)); + return s; +} + +int main() { + cin >> n >> q; + for (int i = 1; i <= n; i++) { + cin >> h[i]; + } + build(1, 1, n); + for (int i = 0; i < q; i++) { + cin >> a >> b; + cout << query_max(1, a, b) - query_min(1, a, b) << endl; + } + return 0; +}