Submission #594900

#	Time	Username	Problem	Language	Result	Execution time	Memory
594900		MadokaMagicaFan	Counting Mushrooms (IOI20_mushrooms)	C++14	10 / 100	233 ms	464 KiB

mushrooms

#include <bits/stdc++.h>

using namespace std;

using ll = long long;
using vi = vector<int>;
using pi = pair<int,int>;

#define all(v)          v.begin(),v.end()
#define sort(v)         sort(all(v))
#define endl            '\n'
#define forn(i,n)       for(int i = 0; i < n; ++i)
#define forbe(i,b,e)    for(int i = b; i < e; ++i)
#define forr(i,n)       for(int i = n-1; i >= 0; --i)
#define sz(v)           ((int)v.size())
#define pb              push_back
#define f               first
#define s               second

int use_machine(vi x);

int count_mushrooms(int n) {
    vi type(n, 1);
    vi s(n,1);
    type[0] = 1;

    while (s[0] < n) {
        for (int i = 0; i < n;) {
            assert(i+s[i] <= n);
            if (i + s[i] == n)
                break;
            
            if (use_machine({i, i + s[i]})) {
                forbe(j, i+s[i], i+s[i]+s[i+s[i]])
                    type[j] = 1 - type[j];
            }

            s[i] += s[i+s[i]];

            i += s[i];
        }
    }

    int ans = 0;
    forn(i, n)
        ans += type[i];
//    forn(i, n)
//        cout << type[i] << ' ';
//        cout << endl;

    return ans;
}

#ifdef ONPC
vi rans;

int use_machine(vi x){
    int _ans = 0;
    forn(i , sz(x)-1)
        if (rans[x[i]] != rans[x[i+1]])
            ++_ans;
    return _ans;
}

void solve() {
    int n;
    cin >> n;

    rans.resize(n);

    char c;

    forn(i, n) {
        cin >> c;
        rans[i]=(c=='A');
    }

    cout << count_mushrooms(n) << endl;
}

int main() {
    freopen("in", "r", stdin);
//    ios_base::sync_with_stdio(0);cin.tie(0);
    solve();
}
#endif

• Subtask 1: 10 / 100