Cow and Snacks
#include <iostream> #include <vector> #include <algorithm> #include <string> #include <set> #include <queue> #include <map> #include <sstream> #include <cstdio> #include <cstring> #include <numeric> #include <cmath> #include <iomanip> #include <deque> #include <bitset> #include <cassert> //#include <unordered_set> #include <unordered_map> #define ll long long #define pii pair<int, int> #define rep(i,a,b) for(int i=a;i<=b;i++) #define dec(i,a,b) for(int i=a;i>=b;i--) #define forn(i, n) for(int i = 0; i < int(n); i++) using namespace std; int dir[4][2] = { { 1,0 },{ 0,1 } ,{ 0,-1 },{ -1,0 } }; const long long INF = 0x7f7f7f7f7f7f7f7f; const int inf = 0x3f3f3f3f; const double pi = acos(-1.0); const double eps = 1e-6; const int mod = 998244353; inline int read() { int x = 0; bool f = true; char c = getchar(); while (c < '0' || c > '9') { if (c == '-') f = false; c = getchar(); } while (c >= '0' && c <= '9') x = (x << 1) + (x << 3) + (c ^ 48), c = getchar(); return f ? x : -x; } inline ll gcd(ll m, ll n) { return n == 0 ? m : gcd(n, m % n); } void exgcd(ll A, ll B, ll& x, ll& y) { if (B) exgcd(B, A % B, y, x), y -= A / B * x; else x = 1, y = 0; } inline ll qpow(ll x, ll n) { int r = 1; while (n > 0) { if (n & 1) r = 1ll * r * x %mod; n >>= 1; x = 1ll * x * x %mod; } return r; } inline int inv(int x) { return qpow(x, mod - 2); } ll lcm(ll a, ll b) { return a * b / gcd(a, b); } /**********************************************************/ const int N = 2e5 + 5; int n, k; bool vis[N]; int f[200010]; int find(int x) { return f[x] == x ? x : f[x] = find(f[x]); } bool add(int x, int y) { int fx = find(x), fy = find(y); if (fx != fy) { f[fx] = fy; return true; } return false; } int main() { cin >> n >> k; vector<vector<int>> g(n); rep(i, 1, n) f[i] = i; rep(i, 1, k) { int u, v; cin >> u >> v; add(u, v); } unordered_map<int,int> mp; rep(i, 1, n) { mp[find(i)]++; } int res = 0; for (auto x : mp) { res += x.second - 1; } cout << k - res << endl; return 0; }