Submission #233281

#	Time	Username	Problem	Language	Result	Execution time	Memory
233281		kartel	Ljetopica (COI19_ljetopica)	C++14	0 / 100	8 ms	384 KiB

ljetopica

#include <bits/stdc++.h>
//#include <ext/pb_ds/assoc_container.hpp>
//#include <ext/pb_ds/tree_policy.hpp>
#define in(x) freopen(x, "r", stdin)
#define out(x) freopen(x, "w", stdout)
#pragma GCC optimize("Ofast")
#pragma GCC optimize("unroll-loops")
#pragma GCC optimize("-O3")
#define F first
#define S second
#define pb push_back
#define N +100500
#define M ll(1e9 + 7)
#define sz(x) (int)x.size()
#define re return
#define oo ll(1e18)
#define el '\n'
#define pii pair <int, int>
using namespace std;
//using namespace __gnu_pbds;
//typedef tree <int, null_type, less_equal <int> , rb_tree_tag, tree_order_statistics_node_update> ordered_set;
typedef long long ll;
typedef long double ld;

ll sm(ll x, ll y) {return (x + y) % M;}

ll bp(ll x, ll y)
{
    if (y == 0) return 1ll;
    if (y % 2) return (bp(x, y - 1) * x) % M;
    ll a = bp(x, y / 2);
    return (a * a) % M;
}

int main()
{
    srand(time(0));
    ios_base::sync_with_stdio(0);
    iostream::sync_with_stdio(0);
    ios::sync_with_stdio(0);
    cin.tie(NULL);
    cout.tie(NULL);

//    in("input.txt");
//    out("output.txt");

    int n, k, i;
    ll ans = 0;
    string s, a, b;
    cin >> n >> k;
    cin >> s;
    cin >> a;
    cin >> b;

    if (k == 0)
    {
        bitset <1005> bt;
        for (i = 0; i <= n; i++) bt[i] = 0;
        bt[0] = 1;
        i = 0;
        while (i < n - 1)
        {
            if (s[i] == 'L')
            {
                bitset <1005> nw;
                for (int i = 1; i <= n; i++) nw[i] = bt[i - 1];
                bt = nw;
            }
            else
            {
                bitset <1005> nw;
                nw[0] = 1;
                for (int i = 1; i <= n; i++) nw[i] = bt[i - 1];
                bt = nw;
            }
            i++;
        }

        reverse(a.begin(), a.end());
        reverse(b.begin(), b.end());


        i = n - 1;
        while (i >= 0 && bt[i] == a[i] - '0') i--;
//        cerr << i << el;
        if (i < 0 || a[i] == '0')
        {
            i = n - 1;
            while (i >= 0 && bt[i] == b[i] - '0') i--;
            if (i < 0 || b[i] == '1')
            {
                i = 0;
                for (i = 0; i < n; i++)
                {
                    if (bt[i]) ans = sm(ans, bp(2, i));
                }
            }
        }
        for (i = 0; i <= n; i++) bt[i] = 1 - bt[i];

        i = n - 1;
        while (i >= 0 && bt[i] == a[i] - '0') i--;
        if (i < 0 || a[i] == '0')
        {
            i = n - 1;
            while (i >= 0 && bt[i] == b[i] - '0') i--;
            if (i < 0 || b[i] == '1')
            {
                i = 0;
                for (i = 0; i < n; i++)
                {
                    if (bt[i]) ans = sm(ans, bp(2, i));
                }
            }
        }
    }
    cout << ans % M;
}

• Subtask 1: 0 / 8
• Subtask 2: 0 / 14
• Subtask 3: 0 / 17
• Subtask 4: 0 / 61