import std.stdio, std.array, std.string, std.conv, std.algorithm; import std.typecons, std.range, std.random, std.math, std.container; import std.numeric, std.bigint, core.bitop, core.stdc.string; immutable long MOD = 10^^9 + 7; void main() { auto N = readln.chomp.to!int; auto G = new int[][](N); foreach (_; 0..N-1) { auto s = readln.split.map!(to!int); G[s[0]-1] ~= s[1]-1; G[s[1]-1] ~= s[0]-1; } assert(0); int ans = 0; auto D = N.iota.map!(i => G[i].length.to!int).array; auto used = new bool[](N); DList!int queue; foreach (i; 0..N) if (D[i] == 1) queue.insertBack(i); while (!queue.empty) { int u = queue.front; queue.removeFront; if (used[u]) continue; used[u] = true; ans += 1; if (D[u] == 0) continue; int v = G[u].map!(v => !used[v]).front; used[v] = true; foreach (w; G[v]) { if (used[w]) continue; D[w] -= 1; if (D[w] <= 1) queue.insertBack(w); } } ans.writeln; }