HDU 5807 Keep In Touch

加维降复杂度

#pragma comment(linker, "/STACK:1024000000,1024000000")
#include<cstdio>
#include<cstring>
#include<cmath>
#include<algorithm>
#include<vector>
#include<map>
#include<set>
#include<queue>
#include<stack>
#include<iostream>
using namespace std;
typedef long long LL;
const double pi=acos(-1.0),eps=1e-8;
void File()
{
    freopen("D:\\in.txt","r",stdin);
    freopen("D:\\out.txt","w",stdout);
}
inline int read()
{
    char c = getchar();  while(!isdigit(c)) c = getchar();
    int x = 0;
    while(isdigit(c)) { x = x * 10 + c - ‘0‘; c = getchar(); }
    return x;
}

const int maxn=50+10;
int mod=998244353;
int T,n,m,k,q,g[maxn][maxn],w[maxn],f[maxn][maxn][maxn][4];

bool check(int a,int b,int c)
{
    if(abs(w[a]-w[b])>k) return 0;
    if(abs(w[a]-w[c])>k) return 0;
    if(abs(w[b]-w[c])>k) return 0;
    return 1;
}

int main()
{
    scanf("%d",&T); while(T--)
    {
        scanf("%d%d%d%d",&n,&m,&k,&q);
        memset(g,0,sizeof g);
        for(int i=1;i<=n;i++) scanf("%d",&w[i]);
        for(int i=1;i<=m;i++)
        {
            int u,v; scanf("%d%d",&u,&v);
            g[u][v]=1;
        }
        memset(f,0,sizeof f);
        for(int i=n;i>=1;i--)
        {
            for(int j=n;j>=1;j--)
            {
                for(int k=n;k>=1;k--)
                {
                    if(check(i,j,k)==0) f[i][j][k][0]=0;
                    else f[i][j][k][0]=(f[i][j][k][0]+1)%mod;

                    for(int s=1;s<k;s++)
                        if(g[s][k]) f[i][j][s][2]=(f[i][j][s][2]+f[i][j][k][0])%mod;

                    for(int s=1;s<=j;s++)
                        if(g[s][j]) f[i][s][k][1]=(f[i][s][k][1]+f[i][j][k][2])%mod;

                    for(int s=1;s<=i;s++)
                        if(g[s][i]) f[s][j][k][0]=(f[s][j][k][0]+f[i][j][k][1])%mod;
                }
            }
        }

        for(int i=1;i<=q;i++)
        {
            int a,b,c; scanf("%d%d%d",&a,&b,&c);
            printf("%d\n",f[a][b][c][0]);
        }
    }
    return 0;
}