[HDOJ5542] The Battle of Chibi (DP, tree-like array)

Title Link: http://acm.hdu.edu.cn/showproblem.php?pid=5542

Test instructions: The number of M is found in N, so that reading from left to right is the ascending subsequence. How many kinds are there in a question?

The DP (I,J) represents the total number of scenarios that take the first I position, a length of J, and the last number as a (i).

The update is easier, DP (I,J) =∑ (k=1->j-1) DP (I-1,K), initialize DP (i,1) = 1.

1#include <bits/stdc++.h>2 using namespacestd;3 #defineLowbit (x) x & (-X)4 5 Const intMoD =int(1e9+7);6 Const intMAXN =1010;7 intDP[MAXN][MAXN];8 intA[MAXN], H[MAXN];9 intN, M, hcnt;Ten  One intSumintIintx) { A     intRET =0; -      while(x) { -RET = (ret + dp[i][x])%MoD; theX-=lowbit (x); -     } -     returnret; - } +  - voidUpdateintIintXintk) { +      while(x <=N) { ADP[I][X] = (dp[i][x] + k)%MoD; atX + =lowbit (x); -     } - } -  - intGetIDintx) { -     returnLower_bound (H, h+hcnt, X)-h; in } -  to intMain () { +     //freopen ("in", "R", stdin); -     intT, _ =1; thescanf"%d", &T); *      while(t--) { $printf"Case #%d:", _++);Panax Notoginsengscanf"%d%d", &n, &m); -          for(inti =1; I <= N; i++) { thescanf"%d", &a[i]); +h[i-1] =A[i]; A         } theSort (h, h+n); hcnt = Unique (h, h+n)-h; +          for(inti =1; I <= N; i++) A[i] = GetID (A[i]) +1; -Memset (DP,0,sizeof(DP)); $          for(inti =1; I <= N; i++) { $             intLo =min (i, m); -              for(intj =1; J <= Lo; J + +) { -                 if(J = =1) { theUpdate (J, A[i],1); -                     Continue;Wuyi                 } the                 intTMP = SUM (J-1, a[i]-1); - Update (J, A[i], TMP); Wu             } -         } Aboutprintf"%d\n", SUM (m, n)); $     } -     return 0; -}

[HDOJ5542] The Battle of Chibi (DP, tree-like array)