#include <cstdio>
#include <queue>
#include <vector>
#define DBG(X)
using namespace std;
int p[200001];
vector<int> edge[200001];
int vis[200001];
int d[200001];
int a[5001];
int g[5001][5001];
int gcd(int a, int b) {
if (!b) return a;
else return gcd(b, a%b);
}
vector<pair<int, int>> edges;
int main()
{
int n;
scanf("%d", &n);
for (int i = 0; i < n; i++)
{
scanf("%d", a + i);
}
for (int i = 0; i < n; i++)
{
for (int j = i + 1; j < n; j++)
{
g[i][j] = gcd(a[i], a[j]);
edges.push_back({i, j});
}
}
vector<vector<int>> edge(n);
long long ret = 0;
for (int i = 0; i < (1 << edges.size()); i++)
{
int ile = 0;
for (int j = 0; j < edges.size(); j++)
{
vis[j] = 0;
if ((1 << j) & i)
{
ile++;
}
}
if (ile != n - 1) continue;
vector<vector<int>> edge(n);
long long z = 1;
for (int j = 0; j < edges.size(); j++)
{
if ((1 << j) & i)
{
int u = edges[j].first;
int v = edges[j].second;
z *= g[u][v];
z %= 1000000007;
edge[u].push_back(v);
edge[v].push_back(u);
}
}
queue<int> Q;
Q.push(0);
while (!Q.empty())
{
int u = Q.front();
vis[u] = 1;
Q.pop();
for (int j = 0; j < edge[u].size(); j++)
{
int v = edge[u][j];
if (!vis[v])
{
Q.push(v);
vis[v] = 1;
}
}
}
int r = 0;
for (int j = 0; j < n; j++)
{
r += vis[j];
}
if (r != n) continue;
ret += z;
ret %= 1000000007;
}
printf("%lld\n", ret);
return 0;
}
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 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 | #include <cstdio> #include <queue> #include <vector> #define DBG(X) using namespace std; int p[200001]; vector<int> edge[200001]; int vis[200001]; int d[200001]; int a[5001]; int g[5001][5001]; int gcd(int a, int b) { if (!b) return a; else return gcd(b, a%b); } vector<pair<int, int>> edges; int main() { int n; scanf("%d", &n); for (int i = 0; i < n; i++) { scanf("%d", a + i); } for (int i = 0; i < n; i++) { for (int j = i + 1; j < n; j++) { g[i][j] = gcd(a[i], a[j]); edges.push_back({i, j}); } } vector<vector<int>> edge(n); long long ret = 0; for (int i = 0; i < (1 << edges.size()); i++) { int ile = 0; for (int j = 0; j < edges.size(); j++) { vis[j] = 0; if ((1 << j) & i) { ile++; } } if (ile != n - 1) continue; vector<vector<int>> edge(n); long long z = 1; for (int j = 0; j < edges.size(); j++) { if ((1 << j) & i) { int u = edges[j].first; int v = edges[j].second; z *= g[u][v]; z %= 1000000007; edge[u].push_back(v); edge[v].push_back(u); } } queue<int> Q; Q.push(0); while (!Q.empty()) { int u = Q.front(); vis[u] = 1; Q.pop(); for (int j = 0; j < edge[u].size(); j++) { int v = edge[u][j]; if (!vis[v]) { Q.push(v); vis[v] = 1; } } } int r = 0; for (int j = 0; j < n; j++) { r += vis[j]; } if (r != n) continue; ret += z; ret %= 1000000007; } printf("%lld\n", ret); return 0; } |
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