HDU 5542 The Battle of Chibi （ccpc 南阳 C）(DP 树状数组 离散化)

#include <iostream>
#include <cstdio>
#include <cstring>
#include <algorithm>
#include <queue>
#include <cmath>
#include <cstdlib>
#include <map>

using namespace std;

const int Mod = 1000000007;
int a[1005];
int b[1005];
int dp[1005][1005];

int sum(int nn, int mm)
{
    int ans=0;
    while(nn)
    {
        ans += dp[nn][mm];
        ans%=Mod;
        nn -= nn&(-nn);
    }
    return ans;
}
void update(int n, int nn, int mm, int x)
{
    while(nn<=n)
    {
        dp[nn][mm] += x;
        dp[nn][mm] %= Mod;
        nn+=nn&(-nn);
    }
}

int main()
{
    int t;
    int n, m;
    scanf("%d", &t);
    for(int tt=1; tt<=t; tt++)
    {
        scanf("%d %d", &n, &m);
        for(int i=1; i<=n; i++)
        {
            scanf("%d", &a[i]);
            b[i] = a[i];
        }
        sort(b+1, b+n+1);
        int k = unique(b+1, b+n+1)-b-1;
        for(int i=1; i<=n; i++)
        {
            a[i] = lower_bound(b+1, b+n+1, a[i])-b;
        }
        memset(dp, 0, sizeof(dp));
        for(int i=1; i<=n; i++)
        {
            for(int j=1; j<=min(i,m); j++)
            {
                if(j==1)
                {
                    update(n, a[i], j, 1);
                    continue;
                }
                int x = sum(a[i]-1, j-1);
                update(n, a[i], j, x);
            }
        }
        int ans = sum(n, m);
        printf("Case #%d: %d\n", tt, ans);
    }

    return 0;
}