結果
| 問題 | No.1418 Sum of Sum of Subtree Size | 
| コンテスト | |
| ユーザー |  | 
| 提出日時 | 2021-03-06 00:37:47 | 
| 言語 | C++17 (gcc 13.3.0 + boost 1.87.0) | 
| 結果 | 
                                AC
                                 
                             | 
| 実行時間 | 49 ms / 2,000 ms | 
| コード長 | 1,052 bytes | 
| コンパイル時間 | 1,933 ms | 
| コンパイル使用メモリ | 200,124 KB | 
| 最終ジャッジ日時 | 2025-01-19 12:10:28 | 
| ジャッジサーバーID (参考情報) | judge5 / judge4 | 
(要ログイン)
| ファイルパターン | 結果 | 
|---|---|
| sample | AC * 3 | 
| other | AC * 41 | 
コンパイルメッセージ
main.cpp: In function ‘int main()’:
main.cpp:15:26: warning: format ‘%lld’ expects argument of type ‘long long int*’, but argument 2 has type ‘i64*’ {aka ‘long int*’} [-Wformat=]
   15 |         i64 n; scanf("%lld", &n);
      |                       ~~~^   ~~
      |                          |   |
      |                          |   i64* {aka long int*}
      |                          long long int*
      |                       %ld
main.cpp:40:20: warning: format ‘%lld’ expects argument of type ‘long long int’, but argument 2 has type ‘i64’ {aka ‘long int’} [-Wformat=]
   40 |         printf("%lld\n", ans);
      |                 ~~~^     ~~~
      |                    |     |
      |                    |     i64 {aka long int}
      |                    long long int
      |                 %ld
main.cpp:15:21: warning: ignoring return value of ‘int scanf(const char*, ...)’ declared with attribute ‘warn_unused_result’ [-Wunused-result]
   15 |         i64 n; scanf("%lld", &n);
      |                ~~~~~^~~~~~~~~~~~
main.cpp:19:22: warning: ignoring return value of ‘int scanf(const char*, ...)’ declared with attribute ‘warn_unused_result’ [-Wunused-result]
   19 |                 scanf("%d%d", &a[i], &b[i]); a[i]--; b[i]--;
      |                 ~~~~~^~~~~~~~~~~~~~~~~~~~~~
            
            ソースコード
#include <bits/stdc++.h>
using namespace std::literals::string_literals;
using i64 = std::int_fast64_t;
using std::cout;
using std::cerr;
using std::endl;
using std::cin;
template<typename T> std::vector<T> make_v(size_t a){return std::vector<T>(a);}
template<typename T, typename... Ts> auto make_v(size_t a, Ts... ts){
  return std::vector<decltype(make_v<T>(ts...))>(a, make_v<T>(ts...));
}
int main() {
	i64 n; scanf("%lld", &n);
	std::vector<int> a(n - 1), b(n - 1);
	std::vector<std::vector<int>> g(n);
	for(int i = 0; i < n - 1; i++) {
		scanf("%d%d", &a[i], &b[i]); a[i]--; b[i]--;
		g[a[i]].push_back(b[i]);
		g[b[i]].push_back(a[i]);
	}
	i64 ans = 0;
	auto solve = [&](auto&& solve, int v, int par) -> i64 {
		i64 ret = 0, sum = 0;
		for(auto to: g[v]) {
			if(to == par) continue;
			i64 val = solve(solve, to, v);
			ans += val - val * val;
			sum += val;
		}
		ans += (n - (sum + 1)) - (n - (sum + 1)) * (n - (sum + 1));
		ans += (n - 1) * (n - 1) + n;
		return sum + 1;
	};
	solve(solve, 0, -1);
	printf("%lld\n", ans);
	return 0;
}
            
            
            
        