#include <algorithm>
#include <bitset>
#include <cassert>
#include <chrono>
#include <complex>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <ctime>
#include <deque>
#include <functional>
#include <iomanip>
#include <iostream>
#include <iterator>
#include <limits>
#include <list>
#include <map>
#include <numeric>
#include <queue>
#include <random>
#include <ratio>
#include <set>
#include <sstream>
#include <stack>
#include <string>
#include <unordered_map>
#include <unordered_set>
#include <utility>
#include <vector>
#include <climits>
#define ll long long
#define ld long double
#define mp make_pair
#define pb push_back
#define in insert
#define vll vector<ll>
#define endl "\n"
#define pll pair<ll,ll>
#define f first
#define s second
#define FOR(i,a,b) for(int i=(a),_b=(b); i<=_b; i++)
#define int ll
#define sz(x) (ll)x.size()
#define all(x) (x.begin(),x.end())
using namespace std;
const ll INF = 1e12;
const ll N =(2e5+5); // TODO : change value as per problem
const ll MOD = 1e9+7;
ll b[N];
ll p[N];
vector<pair<int,int>> adj[N];
map<pll,bool> done;
map<pll,bool> there;
ll dis[N];
void solve(){
ll n,m;
cin >> n >> m;
for(int i =1;i<=m;i++){
cin >> b[i] >> p[i];
b[i]++;
there[{b[i],p[i]}] = true;
}
// path b/w 1 and 2
for(int i =1;i<=m;i++){
if(done[mp(b[i],p[i])]){
continue;
}
for(int j = 1;(b[i] + p[i]*j) <= n;j++){
adj[b[i]].pb({b[i]+p[i]*j,j});
if(there[mp(b[i]+p[i]*j,p[i])]) break;
}
for(int j = 1;(b[i] - p[i]*j) >= 1;j++){
adj[b[i]].pb({b[i]-p[i]*j,j});
if(there[mp(b[i]-p[i]*j,p[i])]) break;
}
done[mp(b[i],p[i])] = true;
}
for(int i =1;i<=n;i++) dis[i] = INF;
dis[1] = 0;
priority_queue<pll,vector<pll>,greater<pll>> pq;
pq.push({0,1});
while(!pq.empty()){
pll P = pq.top();
pq.pop();
for(auto v:adj[P.s]){
if(dis[v.f] > dis[P.s] + v.s){
dis[v.f] = dis[P.s] + v.s;
pq.push({dis[v.f],v.f});
}
}
}
if(dis[2] == INF) dis[2] = -1;
cout << dis[2] << endl;
}
signed main(){
ios_base::sync_with_stdio(0);
cin.tie(NULL);
// freopen(".in","r",stdin);freopen(".out","w",stdout);
ll tt=1;
// cin >> tt;
while(tt--){
solve();
}
}
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
3 ms |
4992 KB |
Output is correct |
2 |
Correct |
3 ms |
4992 KB |
Output is correct |
3 |
Incorrect |
3 ms |
4992 KB |
Output isn't correct |
4 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
3 ms |
4992 KB |
Output is correct |
2 |
Correct |
3 ms |
4992 KB |
Output is correct |
3 |
Incorrect |
3 ms |
4992 KB |
Output isn't correct |
4 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
4 ms |
5120 KB |
Output is correct |
2 |
Correct |
3 ms |
4992 KB |
Output is correct |
3 |
Incorrect |
4 ms |
4992 KB |
Output isn't correct |
4 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
3 ms |
4992 KB |
Output is correct |
2 |
Correct |
4 ms |
4992 KB |
Output is correct |
3 |
Incorrect |
3 ms |
4992 KB |
Output isn't correct |
4 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
3 ms |
4992 KB |
Output is correct |
2 |
Correct |
4 ms |
4992 KB |
Output is correct |
3 |
Incorrect |
4 ms |
4992 KB |
Output isn't correct |
4 |
Halted |
0 ms |
0 KB |
- |