[hdu3308]线段树

题意：单点更新，区间LCIS(最长连续递增序列)查询。具备区间合并维护的性质，不用线段树用什么~

 #pragma comment(linker, "/STACK:10240000,10240000")

 #include <iostream>
 #include <cstdio>
 #include <algorithm>
 #include <cstdlib>
 #include <cstring>
 #include <map>
 #include <queue>
 #include <deque>
 #include <cmath>
 #include <vector>
 #include <ctime>
 #include <cctype>
 #include <set>

 using namespace std;

 #define mem0(a) memset(a, 0, sizeof(a))
 #define lson l, m, rt << 1
 #define rson m + 1, r, rt << 1 | 1
 #define define_m int m = (l + r) >> 1
 #define Rep(a, b) for(int a = 0; a < b; a++)
 #define lowbit(x) ((x) & (-(x)))
 #define constructInt4(name, a, b, c, d) name(int a = 0, int b = 0, int c = 0, int d = 0): a(a), b(b), c(c), d(d) {}
 #define constructInt3(name, a, b, c) name(int a = 0, int b = 0, int c = 0): a(a), b(b), c(c) {}
 #define constructInt2(name, a, b) name(int a = 0, int b = 0): a(a), b(b) {}

 typedef double db;
 typedef long long LL;
 typedef pair<int, int> pii;
 typedef multiset<int> msi;
 typedef multiset<int>::iterator msii;
 typedef set<int> si;
 typedef set<int>::iterator sii;
 typedef vector<int> vi;

 const int dx[] = {, , -, , , , -, -};
 const int dy[] = {, -, , , -, , , -};
 const int maxn = 1e5 + ;
 const int maxm = 1e5 + ;
 const int maxv = 1e7 + ;
 const int MD = 1e9 +;
 const int INF = 1e9 + ;
 const double PI = acos(-1.0);
 const double eps = 1e-;

 int A[maxn];

 struct SegTree {
     struct Node {
         int suflen, prelen, len;
     } tree[maxn << ];

     Node merge(Node a, Node b, int l, int m, int r) {
         Node c;
         int leftLen = m - l + , rightLen = r - m;
         c.prelen = a.prelen;
         if (c.prelen == leftLen && A[m] < A[m + ]) c.prelen += b.prelen;
         c.suflen = b.suflen;
         if (c.suflen == rightLen && A[m] < A[m + ]) c.suflen += a.suflen;
         c.len = a.len;
         c.len = max(c.len, b.len);
         if (A[m] < A[m + ])c.len = max(c.len, a.suflen + b.prelen);
         return c;
     }
     void build(int l, int r, int rt) {
         if (l == r) {
             int x;
             scanf("%d", &x);
             A[l] = x;
             tree[rt].len = tree[rt].prelen =  tree[rt].suflen = ;
             return ;
         }
         define_m;
         build(lson);
         build(rson);
         tree[rt] = merge(tree[rt << ], tree[rt <<  | ], l, m, r);
     }
     void update(int p, int x, int l, int r, int rt) {
         if (l == r) {
             tree[rt].len = tree[rt].prelen =  tree[rt].suflen = ;
             A[l] = x;
             return ;
         }
         define_m;
         if (p <= m) update(p, x, lson);
         else update(p, x, rson);
         tree[rt] = merge(tree[rt << ], tree[rt <<  | ], l, m, r);
     }
     Node query(int L, int R, int l, int r, int rt) {
         if (L <= l && r <= R) return tree[rt];
         define_m;
         if (R <= m) return query(L, R, lson);
         if (L > m) return query(L, R, rson);
         return merge(query(L, m, lson), query(m + , R, rson), L, m, R);
     }
 };

 SegTree st;

 int main() {
     //freopen("in.txt", "r", stdin);
     int T;
     cin >> T;
     while (T--) {
         int n, m;
         cin >> n >> m;
         st.build(, n, );
         for (int i = , u, v; i < m; i++) {
             char s[];
             scanf("%s%d%d", s, &u, &v);
             if (s[] == 'U') {
                 st.update(++u, v, , n, );
             }
             else {
                 printf("%d\n", st.query(++u, ++v, , n, ).len);
             }
         }
     }
     return ;
 }