Submission #63315355

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Source Code Expand

// I AM A MUSLIM

#include "bits/stdc++.h"

#pragma GCC optimize("O3,unroll-loops")
#pragma GCC target("avx2,bmi,bmi2,lzcnt,popcnt")

#define fast_io std::ios::sync_with_stdio(0);std::cin.tie(0)
#define lli long long int
#define flush fflush(stdout)
#define line printf("\n")
#define yn(a, b) printf("%s\n", (a) >= (b) ? "Yes":"No")
#define amodm(a, M) (((a)%M+M)%M)
// #define int lli

using pii = std::pair<int,int>;
using pis = std::pair<int,std::string>;

const int MOD = 1000000007;
const int mxN = 500100;

std::vector<int> g[mxN];
int deg[mxN], vis[mxN];

void dfs(int u, int &cnt) {
    if (vis[u]) return;
    cnt++;
    vis[u] = 1;
    if (deg[u] < 4) return;
    int taken = 0;
    std::vector<int> explore;
    for (auto &v : g[u]) {
        taken++;
        if (vis[v] == 0) explore.push_back(v);
        if (taken == 4) break;
    }
    for (auto &v : explore) dfs(v, cnt);
}

signed main() {
    int testCases=1;
    // scanf("%d",&testCases);
    
    for (int TC = 1; TC <= testCases; TC++) {
        int n;
        scanf("%d",&n);
        for (int i = 0; i < n-1; i++) {
            int u, v;
            scanf("%d%d",&u,&v);
            g[u].push_back(v);
            g[v].push_back(u);
            deg[u]++; deg[v]++;
        }

        for (auto &i : g) {
            sort(i.begin(), i.end(), [] (int a, int b){
                return deg[a] > deg[b];
            });
        }

        int ans = -1;
        for (int i = 1; i <= n; i++) {
            if (vis[i] || deg[i] < 4) continue;
            int cnt = 0;
            dfs(i, cnt);
            if (cnt > ans) ans = cnt;
        }

        printf("%d\n", ans);
        
    }
    
    return 0;
}

Submission Info

Compile Error

./Main.cpp:5:13: warning: unknown pragma ignored [-Wunknown-pragmas]
#pragma GCC optimize("O3,unroll-loops")
            ^
./Main.cpp:6:13: warning: unknown pragma ignored [-Wunknown-pragmas]
#pragma GCC target("avx2,bmi,bmi2,lzcnt,popcnt")
            ^
./Main.cpp:19:11: warning: unused variable 'MOD' [-Wunused-const-variable]
const int MOD = 1000000007;
          ^
3 warnings generated.

Judge Result