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| #include <bits/stdc++.h> using namespace std;
const int N = 1e5 + 5, MOD = 1e9 + 7; int n, m, k, deg[N];
int fpow(int a, int b) { if (b < 0) return 0; int res = 1; for (; b; b >>= 1, a = a * 1ll * a % MOD) if (b & 1) res = res * 1ll * a % MOD; return res; }
namespace baoli { bool b[20][20]; vector<int> e[20]; int F(int s) { memset(b, 0, sizeof b); int res = 0; for (int i = 1; i <= n; i++) { if ((1 << (i - 1)) & s) { for (int j : e[i]) { if (!b[i][j] && (1 << (j - 1) & s)) res = (res + 1) % MOD, b[i][j] = b[j][i] = 1; } } } return res; } void main() { for (int i = 1; i <= n; i++) e[i].clear(); for (int i = 1; i <= m; i++) { int u, v; scanf("%d %d", &u, &v); e[u].push-back(v); e[v].push-back(u); } int res = 0; for (int i = 1; i <= (1 << n) - 1; i++) res = (res + fpow(F(i), k)) % MOD; printf("%d\n", res); exit(0); } } namespace kk { vector<int> e[N]; int vis[N]; struct node { int u, v; }; node v[N]; int calc() { int res = 0; for (int i = 1; i <= m; i++) { if (deg[v[i].u] > deg[v[i].v] || (deg[v[i].u] == deg[v[i].v] && v[i].u < v[i].v)) e[v[i].u].push-back(v[i].v); else e[v[i].v].push-back(v[i].u); } for (int i = 1; i <= n; i++) { for (auto v : e[i]) vis[v] = i; for (auto v : e[i]) for (auto j : e[v]) if (vis[j] == i) res++; } return res; } void main() { for (int i = 1; i <= m; i++) { scanf("%d %d", &v[i].u, &v[i].v); deg[v[i].u]++; deg[v[i].v]++; } int y3 = calc(); int res1 = m * 1ll * fpow(2, n - 2) % MOD; int res = 0; long long tmp = 1ll * m * (m - 1) / 2; for (int i = 1; i <= n; i++) { int w = deg[i]; if (n >= 3) res = (res + 1ll * w * (w - 1) / 2 % MOD * fpow(2, n - 3)) % MOD; tmp -= 1ll * w * (w - 1) / 2; } if (n >= 4) res = (res + tmp % MOD * fpow(2, n - 4)) % MOD; res= res * 2ll % MOD; res = (res + m * 1ll * fpow(2, n - 2) % MOD) % MOD; int ans = (res + MOD - res1) % MOD; ans = ans * 3ll % MOD; ans = ans + res1 % MOD; const int i6 = fpow(6, MOD - 2), i2 = fpow(2, MOD - 2); int cnt4 = MOD - 3 * 1ll * y3 % MOD, cnt5 = 0, cnt6 = 0; for (int i = 1; i <= n; i++) { cnt4 = (cnt4 + deg[i] * 1ll * (deg[i] - 1) % MOD * (deg[i] - 2) % MOD * 1ll * i6 % MOD) % MOD; } for (int i = 1; i <= m; i++) { cnt4 = (cnt4 + (deg[v[i].u] - 1) * 1ll * (deg[v[i].v] - 1) % MOD); } cnt5 = MOD - cnt4 * 2ll % MOD; cnt5 = (cnt5 + MOD - y3 * 1ll * 3 % MOD) % MOD; for (int i = 1; i <= n; i++) { cnt5 = (cnt5 + MOD - deg[i] * 1ll * (deg[i] - 1) % MOD * (deg[i] - 2) % MOD * 1ll * i6 % MOD) % MOD; } for (int i = 1; i <= n; i++) { cnt5 = (cnt5 + (deg[i] - 1) * 1ll * deg[i] % MOD * 1ll * (m - 2) % MOD * i2 % MOD) % MOD; } cnt6 = (m * 1ll * (m - 1) * 1ll * (m - 2) / 6 - y3 - cnt4 - cnt5) % MOD; printf("%lld\n", (ans + 6ll * ((y3 * 1ll * fpow(2, n - 3) % MOD + cnt4 * 1ll * fpow(2, n - 4) % MOD + cnt5 * 1ll * fpow(2, n - 5) % MOD + cnt6 * 1ll * fpow(2, n - 6) % MOD) % MOD) % MOD) % MOD); exit(0); } }
int main() { scanf("%d %d %d", &n, &m, &k); if (n <= 15) baoli::main(); if (k == 3) kk::main(); for (int i = 1; i <= m; i++) { int u, v; scanf("%d %d", &u, &v); deg[u]++, deg[v]++; } if (k == 1) printf("%lld\n", m * 1ll * fpow(2, n - 2) % MOD); else if (k == 2) { int res = 0; long long tmp = 1ll * m * (m - 1) / 2; for (int i = 1; i <= n; i++) { int w = deg[i]; if (n >= 3) res = (res + 1ll * w * (w - 1) / 2 % MOD * fpow(2, n - 3)) % MOD; tmp -= 1ll * w * (w - 1) / 2; } if (n >= 4) res = (res + tmp % MOD * fpow(2, n - 4)) % MOD; res= res * 2ll % MOD; res = (res + m * 1ll * fpow(2, n - 2) % MOD) % MOD; printf("%d\n", res); } return 0; }
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