Submission #280432

#	Time	Username	Problem	Language	Result	Execution time	Memory
280432		Noam13	Toy Train (IOI17_train)	C++14	27 / 100	13 ms	2048 KiB

train

#include <bits/stdc++.h>
#define vi vector<int>
#define vvi vector<vi>
#define vb vector<bool>
#define vvb vector<vb>
#define ii pair<int, int>
#define x first
#define y second
#define vii vector<ii>
#define pb push_back
#define all(x) x.begin(), x.end()
#define loop(i,s,e) for(int i=s;i<e;++i)
#define loopr(i,s,e) for(int i=e-1;i>=s;--i)
#define chkmin(a,b) a = min(a,b)
#define chkmax(a,b) a = max(a,b)
using namespace std;
const int INF = 1e9;


int n;
vb check;
void dfs(int cur, vi& vec, vvi& g){
    if (check[cur]) return ;
    check[cur] = 1; 
    for(auto nei:g[cur]) dfs(nei, vec, g);
    vec.pb(cur);
}
vvi g, ag;

vi solvesmall(vi& a, vi& r){
    return vi(n,0);
}
vi who_wins(vi a, vi r, vi u, vi v) {
    n = a.size();
    g.resize(n); ag.resize(n); check.resize(n);
    loop(i,0,u.size()){
        int a = u[i], b = v[i];
        g[a].pb(b);
        ag[b].pb(a);
    }
    vi res(n);
    //if (n<=15) return solvesmall(a,r);
    bool same = 1;
    loop(i,1,n) if(a[i]!=a[0]) same = 0;
    if (!same){
        res[n-1] = r[n-1];
        loopr(i,0,n-1){
            int tmp = -1;
            res[i] = r[i];
            for(auto nei:g[i]){
                if (nei==i){
                    if ((a[i] ^ r[i]) == 0) tmp = r[i];
                }
                else res[i] = res[nei];
            }
            if (tmp!=-1) res[i] = tmp;
        }
        return res;
    }
    if (a[0]){
        vi order;
        loop(i,0,n) dfs(i, order, ag);
        reverse(all(order)); 
        fill(all(check),0);
        for(auto cur:order){
            if (check[cur]) continue;
            vi vec;
            dfs(cur, vec, g);
            /*for(auto i:vec) cout<<i<<" ";
            cout<<endl;*/
            bool good = 0;
            for(auto i:vec) if (r[i]) good = 1;
            if (vec.size()==1){
                bool self = 0;
                for(auto nei:g[vec[0]]) if (nei==vec[0]) self = 1;
                if (!self) good = 0;
            }
            if (!good){
                for(auto c:vec) for(auto nei:g[c]){
                    if (res[nei]) good = 1;
                }
            }
            for(auto i:vec) res[i] = good;
        }
    }
    else{
        loop(i,0,n) check[i]=r[i];
        vi order;
        loop(i,0,n) dfs(i, order, ag);
        reverse(all(order)); 
        loop(i,0,n) check[i]=r[i];
        for(auto cur:order){
            if (check[cur]) continue;
            vi vec;
            dfs(cur, vec, g);
            bool good = 1;
            if (vec.size()==1){
                good = 0;
                for(auto nei:g[vec[0]]) if (nei==vec[0]) good = 1;
            }
            for(auto i:vec) res[i] = good;
        }
        order.clear();
        fill(all(check),0);
        loop(i,0,n) dfs(i, order, ag);
        reverse(all(order)); 
        fill(all(check),0);
        for(auto cur:order){
            if (check[cur]) continue;
            vi vec;
            dfs(cur, vec, g);
            /*for(auto i:vec) cout<<i<<" ";
            cout<<endl;*/
            bool good = 0;
            for(auto i:vec){
                if (res[i]) good = 1;
                else for(auto nei:g[i]) if(res[nei]) good = 1;
            }
            for(auto i:vec) res[i] = good;
        }
        loop(i,0,n) res[i] = !res[i];
    }
	return res;
}

/*
clear
g++ c.cpp grader.cpp -o c ; ./c
6 7
0 0 0 0 0 0
1 0 0 0 0 1
0 1
1 2
2 3
3 1
4 5
5 5
4 1
*/

Compilation message (stderr)

train.cpp: In function 'std::vector<int> who_wins(std::vector<int>, std::vector<int>, std::vector<int>, std::vector<int>)':
train.cpp:12:34: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   12 | #define loop(i,s,e) for(int i=s;i<e;++i)
......
   36 |     loop(i,0,u.size()){
      |          ~~~~~~~~~~~~             
train.cpp:36:5: note: in expansion of macro 'loop'
   36 |     loop(i,0,u.size()){
      |     ^~~~

• Subtask 1: 5 / 5
• Subtask 2: 0 / 10
• Subtask 3: 11 / 11
• Subtask 4: 11 / 11
• Subtask 5: 0 / 12
• Subtask 6: 0 / 51