Submission #93421

#	Time	Username	Problem	Language	Result	Execution time	Memory
93421		inom	Marriage questions (IZhO14_marriage)	C++14	36 / 100	1584 ms	2936 KiB

marriage

#include<bits/stdc++.h>

#define fi first
#define se second
#define pb push_back
#define int long long
#define sz(c) (int)(c).size()
#define all(c) (c).begin(), (c).end()
#define rall(c) (c).rbegin(), (c).rend()
 
using namespace std;

const int N = 30030;
 
int TN = 1;

int n, m, k;
int cnt, ans;
int us[N][55];
bool flag = false;
vector<int> verr[N];

void rec(int a, int b, int cnt, int pos) {
    if (a > b) {
        if (cnt >= m) {
            flag = true; return;
        } else {
            return;
        }
    }
    if (cnt >= m) {
        flag = true; return;
    }
    for (int i: verr[a]) {
        if (!us[pos][i]) {
            us[pos][i] = 1;
            rec(a + 1, b, cnt + 1, pos);
            us[pos][i] = 0;
        }
    }
    rec(a + 1, b, cnt, pos);
}

void solve() {
    scanf("%lld %lld %lld", &n, &m, &k);
    for (int i = 1; i <= k; i++) {
        int x, y; 
        scanf("%lld %lld", &x, &y); verr[x].push_back(y);
    }
    int pos = 0;
    for (int i = 1; i <= n; i++) {
        int l = i, r = n;
        while (l + 1 < r) {
            int mid = (l + r) >> 1;
            if (mid - i + 1 < m) {
                l = mid + 1; continue;
            }
            flag = false; cnt = 0; pos++;
            rec(i, mid, cnt, pos);
            if (flag) {
                r = mid;
            } else {
                l = mid + 1;
            }
        }
        
        flag = false; cnt = 0; pos++;
        rec(i, r, cnt, pos);
        if (!flag) {
            continue;
        }
        flag = false; cnt = 0; pos++;
        rec(i, l, cnt, pos);
        if (flag) {
            ans += (n - l + 1);
        } else {
            ans += (n - r + 1);
        }
        // cout << i << " " << l << " " << r << "\n";
        /*for (int r = l + m - 1; r <= n; r++) {
            flag = false; cnt = 0;
            rec(l, r, cnt, ans + 1); ans += flag;
            if (flag) {
                ans += (n - r); break;
            }
        }*/
    }
    printf("%lld\n", ans);
    return;
}

signed main() {
    // in; out; // cin >> TN;
    while (TN--) { solve(); }
    return 0;
}

Compilation message (stderr)

marriage.cpp: In function 'void solve()':
marriage.cpp:45:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%lld %lld %lld", &n, &m, &k);
     ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
marriage.cpp:48:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
         scanf("%lld %lld", &x, &y); verr[x].push_back(y);
         ~~~~~^~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 36 / 100