2022“杭电杯”中国大学生算法设计超级联赛（4） Link with Bracket Sequence II

#include

using namespace std;

#define X first
#define Y second
#define eps  1e-2
#define gcd __gcd
#define pb push_back
#define PI acos(-1.0)
#define lowbit(x) (x)&(-x)
#define bug printf("!!!!!\n");
#define mem(x,y) memset(x,y,sizeof(x))

typedef long long LL;
typedef long double LD;
typedef pair<int,int> pii;
typedef unsigned long long uLL;

const int maxn = 505;
const int INF  = 1<<30;
const int mod  = 1e9+7;
#define int long long

int t,n,m;
int f[maxn][maxn];
int a[maxn];
void solve(){
    memset(f,0,sizeof f);
    // memset(g,0,sizeof g);
    scanf("%lld%lld",&n,&m);
    for(int i=1;i<=n;i++) scanf("%lld",&a[i]);
    for(int i=0;i<=n;i++) f[i+1][i]=1;
    for(int i=2;i<=n;i+=2){
        for(int j=1;j+i-1<=n;j++){
            for(int k=j+1;k<=j+i-1;k+=2){
                int l=j,r=j+i-1,e=0;
                if(a[l]==0&&a[k]==0) e=m;
                else if(a[l]<0||a[k]>0) e=0;
                else if(a[l]+a[k]==0) e=1;
                else if((a[l]>0||a[k]<0)&&a[l]*a[k]==0) e=1;
                f[l][r]=(f[l][r]+f[l+1][k-1]*f[k+1][r]%mod*e%mod)%mod;
                
            }
            
        }
    }
    cout<<f[1][n]<<endl;
    
    return;
}

/*
2   
6 1
1 -1 0 -1 -1 1
4 1
-1 1 0 0
*/

int32_t main()
{
   // freopen("C:\Users\Administrator\Desktop\test\test\1001\in.txt","r",stdin);
   // freopen("out.txt","w",stdout);
//    ios::sync_with_stdio(false);
    int t = 1;
    scanf("%lld",&t);
    while(t--){
    //    printf("Case %d: ",cas++);
        solve();
    }
    return 0;
}
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