[題解]hdu_6412公共子序列

https://blog.csdn.net/nka_kun/article/details/81902421

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#include<bits/stdc++.h>
#define ll long long
#define pb push_back
using namespace std;
const ll mod=;
const int maxn=;
int n,k,T,cnt;
ll f[maxn];
vector<int>v[][];
struct node{
    int p[];
//    bool operator <(const node&x)const{
//        for(int i=1;i<=k;i++)
//        if(p[i]<=x.p[i])return 0;
//        return 1;
//    }
    friend bool operator <(node x,node y){
        for(int i=;i<=k;i++)
        if(x.p[i]>=y.p[i])return ;
        return ;
    }
}a[maxn],b;
void dfs(int x,int p){
    if(x==k+)a[++cnt]=b;
    else{
        int s=v[x][p].size();
        for(int i=;i<s;i++){
            b.p[x]=v[x][p][i];
            dfs(x+,p);
        }
    }
}
bool cmp(node a,node b){
    for(int i=;i<=k;i++)
    if(a.p[i]!=b.p[i])return a.p[i]<b.p[i];
    return ;
}
int main(){
    scanf("%d",&T);
    while(T--){
        scanf("%d%d",&k,&n);
        for(int i=;i<=k;i++)
        for(int j=;j<=n;j++)v[i][j].clear();
        cnt=;
        for(int i=;i<=k;i++)
        for(int j=,x;j<=n;j++)scanf("%d",&x),v[i][x].pb(j);//每個數出現位置
        for(int i=;i<=n;i++)
        dfs(,i);

        sort(a+,a+cnt+,cmp);

        for(int i=;i<=cnt;i++)f[i]=;
        for(int i=;i<=cnt;i++)
        for(int j=;j<i;j++)
        if(a[j]<a[i])
        (f[i]+=f[j])%=mod;
        ll ans=;
        for(int i=;i<=cnt;i++)
        (ans+=f[i])%=mod;
        printf("%lld\n",ans);
    }
}