Matrix Multiplication

#include<bits/stdc++.h>

using namespace std;
typedef long long int ll;
//#define isvowel(a) (a == 'a' || a == 'e' || a == 'i' || a == 'o' || a == 'u')
#define pb push_back
#define mp make_pair
#define fi first
#define se second
#define gcd __gcd
#define getl(s) getline(cin, s);
#define setpre(x) fixed << setprecision(x)
#define mset(a) memset(a, 0, sizeof(a))
#define endl '\n'
const int N=200050,M=1000000007;
const ll INF=1e18+7;
vector<vector<ll> > matrix_mul(vector<vector<ll> >A,vector<vector<ll> >B){
    int n=A.size(),m=A[0].size(),mm=B[0].size();
    vector<vector<ll> >C(n,vector<ll>(mm,0));
    for(int i=0;i<n;++i){
        for(int j=0;j<mm;++j){
            for(int p=0;p<m;++p){
                C[i][j]=(C[i][j]+(A[i][p]*B[p][j])%M)%M;
            }
        }
    }
    return C;
}
vector<vector<ll> >divide_and_conquer(vector<vector<ll> >A,ll k){
    if(k==1) return A;
    vector<vector<ll> >B;
    B=divide_and_conquer(A,k/2);
    if(k%2==0) return matrix_mul(B,B);
    return matrix_mul(matrix_mul(B,B),A);
}
int main(){
    ios_base::sync_with_stdio(NULL); cin.tie(nullptr); cout.tie(nullptr);
//    freopen(".inp","r",stdin);
//    freopen(".out","w",stdout);
    ll n,t;
    return 0;
}
/*
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INPUT:                            |
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OUTPUT:                           |
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*/