1674 区间的价值 V2(分治)

 1 # include <cstdio>
 2 # include <cstring>
 3 # include <cstdlib>
 4 # include <iostream>
 5 # include <vector>
 6 # include <queue>
 7 # include <stack>
 8 # include <map>
 9 # include <bitset>
10 # include <sstream>
11 # include <set>
12 # include <cmath>
13 # include <algorithm>
14 using namespace std;
15 # define LL          long long
16 # define pr          pair
17 # define mkp         make_pair
18 # define lowbit(x)   ((x)&(-x))
19 # define PI          acos(-1.0)
20 # define INF         0x3f3f3f3f3f3f3f3f
21 # define eps         1e-8
22 # define MOD         1000000007
23 
24 inline int scan() {
25     int x=0,f=1; char ch=getchar();
26     while(ch<‘0‘||ch>‘9‘){if(ch==‘-‘) f=-1; ch=getchar();}
27     while(ch>=‘0‘&&ch<=‘9‘){x=x*10+ch-‘0‘; ch=getchar();}
28     return x*f;
29 }
30 inline void Out(int a) {
31     if(a<0) {putchar(‘-‘); a=-a;}
32     if(a>=10) Out(a/10);
33     putchar(a%10+‘0‘);
34 }
35 # define MX 100005
36 /**************************/
37 
38 int n;
39 LL ans;
40 int num[MX];
41 int AND[MX];
42 int OR[MX];
43 int tot[MX];
44 
45 void dfs(int l,int r)
46 {
47     if (l==r)
48     {
49         ans = (ans+(LL)num[l]*num[r]%MOD)%MOD;
50         return;
51     }
52     int mid = (l+r+1)>>1;
53     int pos = mid;
54     tot[pos]=0; AND[pos]=OR[pos]=num[pos];
55     for (int i=mid;i<=r;i++)
56     {
57         if ( (num[i]&AND[pos]) != AND[pos] || (num[i]|OR[pos]) != OR[pos] )
58         {
59             pos++;
60             AND[pos] = (num[i]&AND[pos-1]);
61             OR[pos] = (num[i]|OR[pos-1]);
62             tot[pos]=1;
63         }
64         else tot[pos]++;
65     }
66     int tpA = num[mid-1];
67     int tpO = num[mid-1];
68     for (int i=mid-1;i>=l;i--)
69     {
70         tpA&=num[i], tpO|=num[i];
71         for (int j=mid;j<=pos;j++)
72             ans = (ans + ((LL)(tpA&AND[j])*(tpO|OR[j])%MOD) *tot[j]%MOD)%MOD;
73     }
74     dfs(mid,r);
75     dfs(l,mid-1);
76 }
77 
78 int main()
79 {
80     scanf("%d",&n);
81     for (int i=1;i<=n;i++)
82         num[i]=scan();
83     ans = 0;
84     dfs(1,n);
85     printf("%I64d\n",ans);
86     return 0;
87 }