338. Familystrokes | AUTHENTIC — Overview |

Both bounds comfortably meet the limits for N ≤ 10⁵ . Below are clean, self‑contained implementations in C++17 and Python 3 that follow the algorithm exactly. 6.1 C++17 #include <bits/stdc++.h> using namespace std;

internalCnt ← 0 // |I| horizontalCnt ← 0 // # childCount(v) ≥ 2 338. FamilyStrokes

long long internalCnt = 0; // import sys sys.setrecursionlimit(200000) Both bounds comfortably meet the limits for N ≤ 10⁵

while stack: v, p = stack.pop() child_cnt = 0 for w in g[v]: if w == p: continue child_cnt += 1 stack.append((w, v)) if child_cnt: internal += 1 if child_cnt >= 2: horizontal += 1 using namespace std

root = 1 stack = [(root, 0)] # (node, parent) internal = 0 horizontal = 0