计数dp
做不出来真是惭愧。。。
#include <cstdio>
#include <cstdlib>
#include <cmath>
#include <stack>
#include <vector>
#include <sstream>
#include <cstring>
#include <string>
#include <map>
#include <set>
#include <queue>
#include <algorithm>
#include <iostream>
#define FFI freopen("in.txt", "r", stdin)
#define maxn 200010
#define INF 0x3f3f3f3f
#define inf 10000000
#define MOD 1000000007
#define ULL unsigned long long
#define LL long long
#define _setm(houge) memset(houge, INF, sizeof(houge))
#define _setf(houge) memset(houge, -1, sizeof(houge))
#define _clear(houge) memset(houge, 0, sizeof(houge))using namespace std;LL f[1100][1100], g[1100][1100], h[1100][1100];
int a[1100], n;void init() {_clear(f);_clear(g);_clear(h);
}void dp() {f[1][a[1]] = 1;for(int i = 2; i <= n; ++ i) {f[i][a[i]] ++;for(int s = 0; s < 1024; ++ s) {f[i][s^a[i]] += f[i-1][s];f[i][s] += f[i-1][s];f[i][s^a[i]] %= MOD;f[i][s] %= MOD;}}g[n][a[n]] = h[n][a[n]] = 1;for(int i = n-1; i >= 1; -- i) {g[i][a[i]] ++;h[i][a[i]] ++;for(int s = 0; s < 1024; ++ s) {g[i][s&a[i]] += h[i+1][s];h[i][s&a[i]] += h[i+1][s];h[i][s] += h[i+1][s];g[i][s&a[i]] %= MOD;h[i][s&a[i]] %= MOD;h[i][s] %= MOD;}}
}int main()
{int t;scanf("%d", &t);while(t --) {scanf("%d", &n);for(int i = 1; i <= n; ++ i) {scanf("%d", &a[i]);}init();dp();LL ans = 0;for(int i = 1; i < n; ++ i) {for(int j = 0; j < 1024; ++ j) {ans = (ans+f[i][j]*g[i+1][j])%MOD;}}printf("%I64d\n", ans);}return 0;
}
