#pragma GCC optimize ("O3")
#include <bits/stdc++.h>
using namespace std;
//------------------------------DEFINE------------------------------
//******************************************************************
#define IOS ios_base::sync_with_stdio(false); cin.tie(0),cout.tie(0)
#define ll long long
#define pb push_back
#define F first
#define S second
#define INF 1e18
#define all(v) (v).begin(),(v).end()
#define rall(v) (v).rbegin(),(v).rend()
#define pii pair<int,int>
#define pll pair<ll,ll>
#define OK cout<<"Ok"<<endl;
#define MOD (ll)(1e9+7)
#define endl "\n"
//******************************************************************
//----------------------------FUNCTION------------------------------
//******************************************************************
ll gcd(ll a,ll b){
if(a>b) swap(a,b);
if(a==0) return a+b;
return gcd(b%a,a);
}
ll lcm(ll a,ll b){
return a/gcd(a,b)*b;
}
bool is_prime(ll n){
ll k=sqrt(n);
if(n==2) return true;
if(n<2||n%2==0||k*k==n) return false;
for(int i=3;i<=k;i+=2){
if(n%i==0){
return false;
}
}
return true;
}
//*****************************************************************
//--------------------------MAIN-CODE------------------------------
const int mxn=5e3+5;
int t=1,n,m,x[mxn],y[mxn],dis[mxn][mxn],p[mxn*100],nm[mxn*100];
vector<int>vt[mxn];
void bfs(int k){
queue<int>q;
q.push(k);
dis[k][k]=0;
while(q.size()>0){
int u=q.front();
q.pop();
for(int v:vt[u]){
if(dis[k][v]==-1){
dis[k][v]=dis[k][u]+1;
q.push(v);
}
}
}
}
bool fc(pair<pii,int>x,pair<pii,int>y){
if(x.F.F==y.F.F){
return x.F.S>y.F.S;
}
return x.F.F<y.F.F;
}
void solve2(){
vector<pair<pii,int>>vt;
for(int i=1;i<=n;i++){
vt.pb({{x[i],y[i]},i});
}
sort(all(vt),fc);
for(int i=1;i<vt.size();i++){
if(vt[i].F.F<=vt[i-1].F.S&&vt[i-1].F.S<=vt[i].F.S){
p[i]=p[i-1];
}
else{
p[i]=p[i-1]+1;
}
}
for(int i=0;i<vt.size();i++){
nm[vt[i].S]=i;
}
while(m--){
int a,b;
cin>>a>>b;
if(nm[a]<nm[b]&&p[nm[b]]-p[nm[a]]==0){
cout<<nm[b]-nm[a]<<endl;
}
else{
cout<<"impossible"<<endl;
}
}
}
void solve(){
memset(dis,-1,sizeof(dis));
cin>>n>>m;
for(int i=1;i<=n;i++){
cin>>x[i]>>y[i];
}
if(1){
solve2();
return;
}
for(int i=1;i<=n;i++){
for(int j=1;j<=n;j++){
if(x[j]<=y[i]&&y[i]<=y[j]){
vt[i].pb(j);
}
}
}
for(int i=1;i<=n;i++){
bfs(i);
}
while(m--){
int a,b;
cin>>a>>b;
if(dis[a][b]==-1){
cout<<"impossible"<<endl;
}
else{
cout<<dis[a][b]<<endl;
}
}
}
int main(){
IOS;
//cin>>t;
while(t--){
solve();
}
return 0;
}
Compilation message
events.cpp: In function 'void solve2()':
events.cpp:74:18: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<std::pair<int, int>, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
74 | for(int i=1;i<vt.size();i++){
| ~^~~~~~~~~~
events.cpp:82:18: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<std::pair<int, int>, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
82 | for(int i=0;i<vt.size();i++){
| ~^~~~~~~~~~
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
42 ms |
98516 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
39 ms |
98416 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
39 ms |
98416 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
39 ms |
98416 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Runtime error |
116 ms |
199496 KB |
Execution killed with signal 11 |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
42 ms |
98516 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
