Submission #781757

#	Time	Username	Problem	Language	Result	Execution time	Memory
781757		christinelynn	Strange Device (APIO19_strange_device)	C++17	15 / 100	248 ms	32464 KiB

strange_device

#include <bits/stdc++.h>
using namespace std;

# define int long long
# define fir first
# define sec second
# define pb push_back

const int cnst = 2e5+5;
bool mutipletestcase = 0;
//bool debug = false;

int gcd(int a, int b) {return b ? gcd(b, a%b): a;}
int lcm(int a, int b) {return a/gcd(a, b)*b;}

void solve() {
    int n, a, b; cin >> n >> a >> b;

    pair<int, int> num[n+5];
    int length = 0;

    for(int i = 1; i<=n; i++) {
        int x, y; cin >> x >> y;
        length += y-x+1;
        num[i] = {x, y};
    }

    if(length <= 1e6) {
        set<pair<int, int>> st;
        for(int i = 1; i<=n; i++) {
            int x, y; x = num[i].fir, y = num[i].sec;
            for(int i = x; i<=y; i++) {
                st.insert({(i+i/b)%a, i%b});
            }
        }

        cout << st.size() << endl;
        return;
    }
    if(a*b <= 1e6) {
        int val = a*b;
        int ans = 0;
        int get[val*2+5];
        memset(get, 0, sizeof(get));

        for(int i = 1; i<=n; i++) {
            int x, y; x = num[i].fir, y = num[i].sec;
            int len = y-x+1;
            if(len >= a*b) ans = val;
            x %= val;
            y %= val;
            if(!y) y += val;
            if(!x) x += val;
            if(y < x) y += val;
            // cerr << x << " " << y << endl;
            get[x]+=1, get[y+1] -= 1;
        }

        if(ans == val) cout << ans << endl;
        else {
            bool yes[val+5];
            memset(yes, 0, sizeof(yes));

            for(int i = 1; i<=2*val; i++) {
                get[i] += get[i-1];
                // cerr << i << " " << get[i] << " " << endl;
                // if(get[i]) cerr << i << " ";
                if(get[i]) yes[i%val] = 1;
            }
            for(int i = 0; i<=val; i++) {
                if(yes[i]) ans++;
            }

            cout << ans << endl;
        }
        return;
    }

}

signed main() {
    ios_base::sync_with_stdio(false);
    int t = 1;
    if(mutipletestcase) cin >> t; 
    while(t--) solve();
}

• Subtask 1: 10 / 10
• Subtask 2: 0 / 5
• Subtask 3: 5 / 5
• Subtask 4: 0 / 5
• Subtask 5: 0 / 5
• Subtask 6: 0 / 20
• Subtask 7: 0 / 20
• Subtask 8: 0 / 30