//Never stop trying
#pragma GCC target ("avx2")
#pragma GCC optimization ("O3")
#pragma GCC optimization ("unroll-loops")
#include <bits/stdc++.h>
using namespace std;
#define boost ios_base::sync_with_stdio(false); cin.tie(0); cout.tie(0)
typedef string str;
typedef long long ll;
typedef double db;
typedef long double ld;
typedef pair<int, int> pi;
#define fi first
#define se second
typedef vector<int> vi;
typedef vector<pi> vpi;
typedef vector<str> vs;
typedef vector<ld> vd;
#define pb push_back
#define sz(x) (int)x.size()
#define all(x) begin(x), end(x)
#define rall(x) rbegin(x), rend(x)
#define endl "\n"
#define FOR(i,a,b) for (int i = (a); i < (b); ++i)
#define F0R(i,a) FOR(i,0,a)
#define ROF(i,a,b) for (int i = (b)-1; i >= (a); --i)
#define R0F(i,a) ROF(i,0,a)
const int MOD = 1e9 + 7; //998244353
const ll INF = 1e18;
const int MX = 2e5 + 10;
const int nx[4] = {0, 0, 1, -1}, ny[4] = {1, -1, 0, 0}; //right left down up
template<class T> using V = vector<T>;
template<class T> bool ckmin(T& a, const T& b) { return a > b ? a = b, 1 : 0; }
template<class T> bool ckmax(T& a, const T& b) { return a < b ? a = b, 1 : 0; }
ll cdiv(ll a, ll b) { return a / b + ((a ^ b) > 0 && a % b); } // divide a by b rounded up
constexpr int log2(int x) { return 31 - __builtin_clz(x); } // floor(log2(x))
#define dbg(x) cerr << " - " << #x << " : " << x << endl;
#define dbgs(x,y) cerr << " - " << #x << " : " << x << " / " << #y << " : " << y << endl;
#define dbgv(v) cerr << " - " << #v << " : " << endl << "[ "; for(auto it : v) cerr << it << ' '; cerr << ']' << endl;
void IO() {
#ifndef ONLINE_JUDGE
freopen("input.txt", "r", stdin);
freopen("output.txt", "w", stdout);
#endif
}
#define ull unsigned ll
ll N,A,B;
ll determine(){
ll x=A/(__gcd(A,(B+1)%A));
ll y=B;
if(log10(x)+log10(y)>18.5) return -1;
return x*y;
}
pair<ll,ll> inter(pair<ll,ll> a, pair<ll,ll> b){
/*dbgs(a.fi,a.se);
dbgs(b.fi,b.se);*/
if(a.fi==-1ll) return b;
if(b.se<a.fi || a.se<b.fi) return {-1ll,-1ll};
return {min(a.fi,b.fi),max(a.se,b.se)};
}
int main() {
boost;
cin>>N>>A>>B;
ll X=determine();
V<pair<ll,ll>> vec;
FOR(i,0,N){
int l,r; cin>>l>>r;
if(X==-1) vec.pb({l,r});
else{
if(r-l>=X) vec.pb({0,X-1});
else{
l%=X; r%=X;
if(l<=r) vec.pb({l,r});
else vec.pb({l,X-1}),vec.pb({0,r});
}
}
}
sort(all(vec));
//for(auto x: vec) cout << x.fi << ' ' << x.se << endl;
V<pair<ll,ll>> res;
ll l=-1,r=-1;
FOR(i,0,sz(vec)){
pair<ll,ll> p=inter({l,r},{vec[i].fi,vec[i].se});
//dbgs(p.fi,p.se);
if(p.fi!=-1){
l=p.fi; r=p.se;
}
else{
res.pb({l,r});
l=vec[i].fi,r=vec[i].se;
}
}
if(l!=-1) res.pb({l,r});
//for(auto x: res) cout << x.fi << ' ' << x.se << endl;
ll ans=0;
for(auto x: res) ans+=x.se-x.fi+1;
cout << ans << endl;
return 0;
}
/* Careful!!!
.Array bounds
.Infinite loops
.Uninitialized variables / empty containers
.Order of input
Some insights:
.Binary search
.Graph representation
.Write brute force code
.Change your approach
*/
Compilation message
strange_device.cpp:3: warning: ignoring #pragma GCC optimization [-Wunknown-pragmas]
3 | #pragma GCC optimization ("O3")
|
strange_device.cpp:4: warning: ignoring #pragma GCC optimization [-Wunknown-pragmas]
4 | #pragma GCC optimization ("unroll-loops")
|
strange_device.cpp: In function 'void IO()':
strange_device.cpp:49:9: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
49 | freopen("input.txt", "r", stdin);
| ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~
strange_device.cpp:50:9: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
50 | freopen("output.txt", "w", stdout);
| ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
1 ms |
384 KB |
Output is correct |
| 2 |
Incorrect |
2 ms |
1024 KB |
Output isn't correct |
| 3 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
1 ms |
384 KB |
Output is correct |
| 2 |
Correct |
1 ms |
384 KB |
Output is correct |
| 3 |
Correct |
1 ms |
384 KB |
Output is correct |
| 4 |
Incorrect |
0 ms |
384 KB |
Output isn't correct |
| 5 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
0 ms |
384 KB |
Output is correct |
| 2 |
Incorrect |
1 ms |
384 KB |
Output isn't correct |
| 3 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
1 ms |
384 KB |
Output is correct |
| 2 |
Incorrect |
138 ms |
33348 KB |
Output isn't correct |
| 3 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
1 ms |
384 KB |
Output is correct |
| 2 |
Incorrect |
138 ms |
33348 KB |
Output isn't correct |
| 3 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
1 ms |
384 KB |
Output is correct |
| 2 |
Incorrect |
138 ms |
33348 KB |
Output isn't correct |
| 3 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
0 ms |
384 KB |
Output is correct |
| 2 |
Incorrect |
12 ms |
4596 KB |
Output isn't correct |
| 3 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
1 ms |
384 KB |
Output is correct |
| 2 |
Incorrect |
2 ms |
1024 KB |
Output isn't correct |
| 3 |
Halted |
0 ms |
0 KB |
- |
