UVA : 11486 - Finding Paths in Grid (Matrix expo, math)

UVA : 11486 - Finding Paths in Grid (Matrix expo, math)

///==================================================///
/// !! HELLO WORLD !! ///
/// IT'S ME - BISHAL GAUTAM ///
/// [ bsal.gautam16@gmail.com ] ///
///==================================================///
#include<bits/stdc++.h>
#define X first
#define Y second
#define mpp make_pair
#define pll pair<ll,ll>
#define pii pair<int,int>
#define pb(x) push_back(x)
#define nl printf("\n")
#define Max(a,b) ((a>b)?a:b)
#define Min(a,b) ((a<b)?a:b)
#define SZ(x) (int)(x.size())
///---------------------
#define S(a) scanf("%d",&a)
#define P(a) printf("%d",a)
#define SL(a) scanf("%lld",&a)
#define S2(a,b) scanf("%d%d",&a,&b)
#define SL2(a,b) scanf("%lld%lld",&a,&b)
///------------------------------------
#define all(v) v.begin(),v.end()
#define CLR(a) memset(a,0,sizeof(a))
#define SET(a) memset(a,-1,sizeof(a))
#define fr(i,a,n) for(int i=a;i<=n;i++)
using namespace std;
typedef long long ll;

/// Digit 0123456789012345678 ///
#define MX 38
#define inf 2000000010
#define eps 1e-9
#define MD 1000000007
///===============================///

#define N 37
int ms;///Matrix Size GLOBAL: N
struct mat {
ll m[N][N];
mat() {};
void Nullify( ) {
for(int i=0; i<ms; i++) {
for(int j=0; j<ms; j++) {
m[i][j]=0;
}
}
}
void Unify( ) {
for(int i=0; i<ms; i++) {
for(int j=0; j<ms; j++) {
m[i][j]=(i==j);
}
}
}
mat operator *(const mat &b )const {
mat c;
for(int i=0; i<ms; i++) {
for(int j=0; j<ms; j++) {
c.m[i][j]=0;
for(int k=0; k<ms; k++) {
c.m[i][j]=( c.m[i][j]+ (m[i][k]*b.m[k][j])%MD )%MD;
}
}
}
return c;
}
mat Pow(int p) {
mat ret;
ret.Unify();
mat B=(*this);
for(; p; p>>=1) {
if(p & 1)ret = (ret * B);
B = (B * B);
}
return ret;
}
void Print( ) {
cout<<endl;
cout<< "Matix is:\n";
cout<< "****************************\n";
for(int i=0; i<ms; i++) {
for(int j=0; j<ms; j++) {
cout<<m[i][j]<< " ";
}
cout<<endl;
}
cout<< "****************************\n";
cout<<endl;
}
} b;

int MP[7][7][7][7];
vector< vector<int> >v;
void Precal( ) {
for(int a=0; a<7; a++) {
for(int b=a+1; b<7; b++) {
for(int c=b+1; c<7; c++) {
for(int d=c+1; d<7; d++) {
vector<int>tp;
tp.pb(a);
tp.pb(b);
tp.pb(c);
tp.pb(d);
v.pb( tp );
}
}
}
}
ms=SZ(v);
for(int i=0; i<ms; i++) {
MP[ v[i][0] ][ v[i][1] ][ v[i][2] ][ v[i][3] ]=i;
for(int j=0; j<ms; j++) {
vector<int>tmp=v[j];
int tot=0;
do {
int cnt=0;
for(int k=0; k<4; k++) {
if( abs( v[i][k]-tmp[k] ) ==1 )cnt++;
}
if(cnt==4) tot++;

} while( next_permutation(all(tmp)) );

b.m[ i ][ j ]=tot;
}
}
}


int a[10];
int main() {
int tc,cs=1,i,j,k,n,r,x;
b.Nullify();
Precal( );
S(tc);
while(tc--) {
S(n);
CLR(a);
k=0;
for(i=0;i<7;i++){
S(x);
if(x)a[k++]=i;
}
int id=MP[ a[0] ][ a[1] ][ a[2] ][ a[3] ];
n--;
mat ret=b.Pow( n );
ll ans=0;
for(i=0;i<ms;i++){
ans=(ans+ret.m[ id ][ i ])%MD;
}
printf("%lld\n",ans);
}
return 0;
}

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