小a和uim之大逃离

Posted 2021-02-16 acm1ruoji

题目传送门

#include <bits/stdc++.h>
using namespace std;
#define ll long long
#define re register
#define fi first
#define se second
#define mp make_pair
#define pb push_back
#define P pair<int,int>
const int N=1e9;
const int mod=1e9+7;
void read(int &a)
{
    a=0;
    int d=1;
    char ch;
    while(ch=getchar(),ch>‘9‘||ch<‘0‘)
        if(ch==‘-‘)
            d=-1;
    a=ch-‘0‘;
    while(ch=getchar(),ch>=‘0‘&&ch<=‘9‘)
        a=a*10+ch-‘0‘;
    a*=d;
}
void write(int x)
{
    if(x<0)
        putchar(45),x=-x;
    if(x>9)
        write(x/10);
    putchar(x%10+‘0‘);
}
int f[805][805][20][2],a[805][805];
int main()
{
    int n,m,k;
    read(n);
    read(m);
    read(k);
    k++;
    for(re int i=1;i<=n;i++)
        for(re int j=1;j<=m;j++)
            read(a[i][j]),f[i][j][a[i][j]%k][0]=1;
    for(re int i=1;i<=n;i++)
        for(re int j=1;j<=m;j++)
            for(re int h=0;h<=k;h++)
            {
                f[i][j][h][0]=(f[i][j][h][0]+f[i-1][j][(h-a[i][j]+k)%k][1])%mod;
                f[i][j][h][0]=(f[i][j][h][0]+f[i][j-1][(h-a[i][j]+k)%k][1])%mod;
                f[i][j][h][1]=(f[i][j][h][1]+f[i-1][j][(h+a[i][j])%k][0])%mod;
                f[i][j][h][1]=(f[i][j][h][1]+f[i][j-1][(h+a[i][j])%k][0])%mod;
            }
    ll ans=0;
    for(re int i=1;i<=n;i++)
        for(re int j=1;j<=m;j++)
            ans=(ans+f[i][j][0][1])%mod;
    printf("%lld",ans);
    return 0;
}