제출 #383375

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
383375		LucaDantas	Bitaro’s Party (JOI18_bitaro)	C++17	14 / 100	92 ms	14080 KiB

bitaro

// Q = 1, brute dfs solution
#include <bits/stdc++.h>
using namespace std;

constexpr int maxn = 1e5+10;

vector<int> g[maxn]; // reverse

bool busy[maxn], tem[maxn];

int dp[maxn];

int dfs(int u) {
	if(dp[u] != -1) return dp[u];
	tem[u] = !busy[u];
	int& ans = dp[u];
	ans = 0;
	for(int v : g[u])
		ans = max(ans, dfs(v)+tem[v]), tem[u] |= tem[v];
	return ans;
}

int main() {
	int n, m, q; scanf("%d %d %d", &n, &m, &q); // assert(q == 1);
	for(int i = 0, a, b; i < m; i++)
		scanf("%d %d", &b, &a), g[a].push_back(b);
	memset(dp, -1, sizeof dp);
	int t, y; scanf("%d %d", &t, &y);
	for(int i = 0, a; i < y; i++)
		scanf("%d", &a), busy[a] = 1;
	printf("%d\n", dfs(t)==0&&busy[t]?-1:dfs(t));
}

컴파일 시 표준 에러 (stderr) 메시지

bitaro.cpp: In function 'int main()':
bitaro.cpp:24:20: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   24 |  int n, m, q; scanf("%d %d %d", &n, &m, &q); // assert(q == 1);
      |               ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
bitaro.cpp:26:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   26 |   scanf("%d %d", &b, &a), g[a].push_back(b);
      |   ~~~~~^~~~~~~~~~~~~~~~~
bitaro.cpp:28:17: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   28 |  int t, y; scanf("%d %d", &t, &y);
      |            ~~~~~^~~~~~~~~~~~~~~~~
bitaro.cpp:30:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   30 |   scanf("%d", &a), busy[a] = 1;
      |   ~~~~~^~~~~~~~~~

• Subtask 1: 7 / 7
• Subtask 2: 7 / 7
• Subtask 3: 0 / 86