Submission #7865823

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Source Code Expand

#include<iostream>
#include<string>
#include<cstdio>
#include<vector>
#include<cmath>
#include<algorithm>
#include<functional>
#include<iomanip>
#include<queue>
#include<ciso646>
#include<random>
#include<map>
#include<set>
#include<complex>
#include<bitset>
#include<stack>
#include<unordered_map>
#include<utility>
#include<tuple>
using namespace std;
typedef long long ll;
typedef unsigned int ui;
const ll mod = 1000000007;
const ll INF = (ll)1000000007 * 1000000007;
typedef pair<int, int> P;
#define stop char nyaa;cin>>nyaa;
#define rep(i,n) for(int i=0;i<n;i++)
#define per(i,n) for(int i=n-1;i>=0;i--)
#define Rep(i,sta,n) for(int i=sta;i<n;i++)
#define Per(i,sta,n) for(int i=n-1;i>=sta;i--)
#define rep1(i,n) for(int i=1;i<=n;i++)
#define per1(i,n) for(int i=n;i>=1;i--)
#define Rep1(i,sta,n) for(int i=sta;i<=n;i++)
typedef long double ld;
typedef complex<ld> Point;
const ld eps = 1e-8;
const ld pi = acos(-1.0);
typedef pair<ll, ll> LP;

int n;
int c[210]={-1};
string s[210];
vector<int> G[210];


void solve(){
    cin >> n;
    rep(i,n){
        cin >> s[i];
        c[i]=-1;
    }
    rep(i,n){
        rep(j,n){
            if (s[i][j]=='1') G[i].push_back(j);
        }
    }
    queue<P> que;
    que.push(P(0,1)); 
    c[0]=1;
    int ans=0;
    rep(i,n){
        rep(j,n){
            c[j]=-1;
        }
        queue<P> que;
        que.push(P(i,1)); 
        c[i]=1;
    while(!que.empty()){
        int s=que.front().first,k=que.front().second;que.pop();
        //cout << s << " " << k << endl;
        for(int t:G[s]){
            //cout << t << endl;
            if (c[t]!=-1){
                 if (abs(c[t]-c[s])!=1) {
                     cout << -1 << endl;
                     return;
                 }
                 else continue;
            }
            c[t]=k+1;
            que.push(P(t,k+1));
        }
    }
    
    rep(i,n){
        //cout << i << endl;
        ans=max(ans,c[i]);
    }
    }
    cout << ans << endl;
}

int main(){
    ios::sync_with_stdio(false);
    cin.tie(0);
    cout << fixed << setprecision(50);
    solve();
}

Submission Info

Judge Result