cf 1051 Div.2 D1. Inversion Graph Coloring (Easy Version)

#include<bits/stdc++.h>
using namespace std;

typedef long long LL;
const int maxn = 300 + 100;
const LL MOD = 1000000007;
int T, n;
LL ans;
int a[maxn];
LL dp[maxn][maxn][maxn];

int main(){
#ifdef ExRoc
    freopen("test.txt", "r", stdin);
#endif // ExRoc
    ios::sync_with_stdio(false);

    cin >> T;
    while (T--) {
        cin >> n;
        for (int i = 1; i <= n; ++i) {
            cin >> a[i];
        }
        dp[0][0][0] = 1;
        for (int i = 1; i <= n; ++i) {
            memcpy(dp[i], dp[i - 1], sizeof(dp[i]));
            for (int sec = 0; sec < a[i]; ++sec) {
                for (int mx = sec; mx <= a[i]; ++mx) {
                    dp[i][a[i]][sec] = (dp[i][a[i]][sec] + dp[i - 1][mx][sec]) % MOD;
                }
            }
            for (int mx = a[i] + 1; mx <= n; ++mx) {
                for (int sec = 0; sec <= a[i]; ++sec) {
                    dp[i][mx][a[i]] = (dp[i][mx][a[i]] + dp[i - 1][mx][sec]) % MOD;
                }
            }
        }
        ans = 0;
        for (int i = 0; i <= n; ++i) {
            for (int j = 0; j <= n; ++j) {
                ans = (ans + dp[n][i][j]) % MOD;
            }
        }
        cout << ans << endl;
    }

    return 0;
}