#include <bits/stdc++.h>
typedef long long ll;
#define endl '\n'
//#define int ll
using namespace std;
const int N=5010;
const ll mod=1000'000'007;
ll binpow(ll a,ll b){
if (!b) return 1ll;
if (b%2) return binpow(a,b-1)*a%mod;
else return binpow(a*a%mod,b/2ll);
}
int dsu[N];
int get(int x){
if (x==dsu[x]) return x;
return dsu[x]=get(dsu[x]);
}
ll a[N][N];
ll Det(int n){
ll ans=1ll;
for (int i=1;i<=n;i++){
if (a[i][i]==0){
for (int j=i+1;j<=n;j++){
if (a[j][i]){
for (int t=1;t<=n;t++){
swap(a[i][t],a[j][t]);
}
break;
}
}
ans=mod-ans;
}
if (a[i][i]==0){
ans=0;
break;
}
ll inv=binpow(a[i][i],mod-2);
ans*=a[i][i];
ans%=mod;
for (int j=1;j<=n;j++){
a[i][j]*=inv;
a[i][j]%=mod;
}
for (int j=i+1;j<=n;j++){
ll c=a[j][i];
for (int t=1;t<=n;t++){
a[j][t]-=a[i][t]*c;
a[j][t]%=mod;
a[j][t]+=mod;
a[j][t]%=mod;
}
}
}
for (int i=1;i<=n;i++){
ans*=a[i][i];
ans%=mod;
}
return ans;
}
ll x[N];
ll d[N];
void solve(){
int n;cin>>n;
for (int i=1;i<=n;i++) cin>>x[i];
for (int i=1;i<=n;i++){
for (int j=1;j<=n;j++){
if (i!=j){
a[i][j]=-__gcd(x[i],x[j]);
a[i][i]-=a[i][j];
}
}
}
ll ans=Det(n-1);
cout<<ans<<'\n';
}
int32_t main()
{
ios_base::sync_with_stdio(false);
cin.tie(0);
int tt=1;
while (tt--){
solve();
}
return 0;
}
/**
5
2 3 6 12 4
5345
175,4644,51940
**/
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 | #include <bits/stdc++.h> typedef long long ll; #define endl '\n' //#define int ll using namespace std; const int N=5010; const ll mod=1000'000'007; ll binpow(ll a,ll b){ if (!b) return 1ll; if (b%2) return binpow(a,b-1)*a%mod; else return binpow(a*a%mod,b/2ll); } int dsu[N]; int get(int x){ if (x==dsu[x]) return x; return dsu[x]=get(dsu[x]); } ll a[N][N]; ll Det(int n){ ll ans=1ll; for (int i=1;i<=n;i++){ if (a[i][i]==0){ for (int j=i+1;j<=n;j++){ if (a[j][i]){ for (int t=1;t<=n;t++){ swap(a[i][t],a[j][t]); } break; } } ans=mod-ans; } if (a[i][i]==0){ ans=0; break; } ll inv=binpow(a[i][i],mod-2); ans*=a[i][i]; ans%=mod; for (int j=1;j<=n;j++){ a[i][j]*=inv; a[i][j]%=mod; } for (int j=i+1;j<=n;j++){ ll c=a[j][i]; for (int t=1;t<=n;t++){ a[j][t]-=a[i][t]*c; a[j][t]%=mod; a[j][t]+=mod; a[j][t]%=mod; } } } for (int i=1;i<=n;i++){ ans*=a[i][i]; ans%=mod; } return ans; } ll x[N]; ll d[N]; void solve(){ int n;cin>>n; for (int i=1;i<=n;i++) cin>>x[i]; for (int i=1;i<=n;i++){ for (int j=1;j<=n;j++){ if (i!=j){ a[i][j]=-__gcd(x[i],x[j]); a[i][i]-=a[i][j]; } } } ll ans=Det(n-1); cout<<ans<<'\n'; } int32_t main() { ios_base::sync_with_stdio(false); cin.tie(0); int tt=1; while (tt--){ solve(); } return 0; } /** 5 2 3 6 12 4 5345 175,4644,51940 **/ |
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