Submission #1267532

#	Time	Username	Problem	Language	Result	Execution time	Memory
1267532		ilovewaguri	Cutting a Rectangle (BOI24_rectangle)	C++20	0 / 100	44 ms	11968 KiB

Main

#include<bits/stdc++.h>
using namespace std;
#define NAME "REGTANGLE"
#define nl '\n'
#define mset(x,val) memset(x,val,sizeof(x))
typedef long long ll;
const int MAXN = (int)5e6+5;

int w[MAXN], h[MAXN];
bool visited[MAXN];
vector<int> big[MAXN], small[MAXN];
int K;
ll area;

void ccps() {
    ios_base::sync_with_stdio(0);
    cin.tie(0);cout.tie(0);
    if(fopen(NAME".inp","r")) {
        freopen(NAME".inp","r",stdin);
        freopen(NAME".out","w",stdout);
    }
}

bool check_pair(int a, int b) {
    mset(visited,false);
    while(true) {
        bool ok = false;
        if (a < b) swap(a,b);
        if (a < MAXN) {
            for (int idx : big[a]) {
                if (!visited[idx]) {
                    visited[idx] = true;
                    b -= h[idx];
                    ok = true;
                }
            }
        }
        if (ok) continue;
        if (b < MAXN) {
            for (int idx : small[b]) {
                if (!visited[idx]) {
                    visited[idx] = true;
                    a -= w[idx];
                    ok = true;
                }
            }
        }
        if (ok) continue;
        if (b < MAXN) {
            for (int idx : big[b]) {
                if (!visited[idx]) {
                    visited[idx] = true;
                    a -= h[idx]; 
                    ok = true;
                }
            }
        }
        if (!ok) break;
    }
    return (a * b == 0);
}

signed main() {
    ccps();
    cin >> K;
    area = 0;
    for (int i = 1; i <= K; i++) {
        cin >> w[i] >> h[i];
        area += 1LL * w[i] * h[i];
        big[w[i]].push_back(i);
        small[h[i]].push_back(i);
    }
    vector<int> res;
    for (ll len = 1; len * len <= area; len++) {
        if (area % len == 0) {
            ll a = len, b = area / len;
            if (a <= b && check_pair(a,b)) res.push_back(a);
            if (a != b && b <= a && check_pair(b,a)) res.push_back(b);
        }
    }
    cout << (int)res.size() << nl;
    for (int x : res) cout << x << nl;
}

Compilation message (stderr)

Main.cpp: In function 'void ccps()':
Main.cpp:19:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   19 |         freopen(NAME".inp","r",stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~
Main.cpp:20:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   20 |         freopen(NAME".out","w",stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 0 / 25
• Subtask 2: 0 / 20
• Subtask 3: 0 / 55