| # | Time | Username | Problem | Language | Result | Execution time | Memory |
|---|---|---|---|---|---|---|---|
| 410622 | dynam1c | Strange Device (APIO19_strange_device) | C++17 | 0 ms | 0 KiB |
This submission is migrated from previous version of oj.uz, which used different machine for grading. This submission may have different result if resubmitted.
//#pragma comment(linker, "/stack:200000000")
//#pragma GCC optimize("Ofast")
//#pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,tune=native")
#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
#define endl "\n"
#define all(c) (c).begin(),(c).end()
// when you ponder, divide and conquer
#define lo __int128
lo gcd(lo x, lo y) {
if (x == 0) return y;
return gcd(y % x, x);
}
signed main() {
// freopen("input.txt", "r", stdin); freopen("output.txt", "w", stdout);
std::ios::sync_with_stdio(false);
cin.tie(0);
ll n, a, b;
cin >> n >> a >> b;
lo g = gcd(b+1, (lo) a * b);
lo m = (lo) a * b / g;
vector<pair<lo, int>> evs;
for (int i = 0; i < n; i++) {
ll xl, xr;
cin >> xl >> xr;
xr++;
lo l = xl % m;
lo r = xr % m;
if (r < l)
evs.emplace_back(0, 1), evs.emplace_back(r, -1), evs.emplace_back(l, 1), evs.emplace_back(m, -1);
else
evs.emplace_back(l, 1), evs.emplace_back(r, -1);
}
sort(all(evs));
ll res = 0;
lo p = 0;
int c = 0;
for (auto [x, t] : evs) {
if (c == 0) p = x;
c += t;
if (c == 0) res += x-p;
}
cout << res << endl;
}
/* --- PSolving ---
* Simplifying (getting rid of variables, conditions, code logic, etc.)
* Reframing
* Solving a subtask (subgoal, aux. problem, removing a condition or fixing a parameter, etc.)
* Inducing
* Divide and conquer
* Working backwards
* Visual intuition
* !! Reductions don't have to be specializations, they can be generalizations
*/