#include <bits/stdc++.h>
using namespace std;
#pragma GCC target ("avx2")
#pragma GCC optimization ("O3")
#pragma GCC optimization ("unroll-loops")
#define flash ios_base::sync_with_stdio(false); cin.tie(0); cout.tie(0)
#define debug(x) cerr << " - " << #x << ": " << x << endl;
#define debugs(x, y) cerr << " - " << #x << ": " << x << " " << #y << ": " << y << endl;
#define all(x) (x).begin(),(x).end()
#define sz(x) (ll)x.size()
#define ll long long
#define INF 1000000000
#define MOD 1000000007
#define pb push_back
#define ve vector<ll>
#define dos pair<ll,ll>
#define vedos vector<dos>
#define rand mt19937 rng(chrono::steady_clock::now().time_since_epoch().count())
struct greateri
{
template<class T>
bool operator()(T const &a, T const &b) const { return a > b; }
};
ll n,v;
vector<ll>scrapes[2020];
bool vis[2020][30011];
ll power[30011],dist[2020][30011];
int main()
{
//flash;
cin>>n>>v;
ll rooto,dest;
for (ll i = 0; i < v; ++i)
{
ll x,y;
cin>>x>>power[i];
if(!vis[x][power[i]])scrapes[x].pb(power[i]);
vis[x][power[i]]=1;
if(!i)rooto=x;
else if(i==1)dest=x;
}
for (ll i = 0; i < n; ++i)
{
for (ll j = 0; j < v; ++j)
{
dist[i][j]=INF;
}
}
priority_queue<pair<ll,pair<ll,ll>>,vector<pair<ll,pair<ll,ll>>>,greater<pair<ll,pair<ll,ll>>>>g;
for (ll i = 0; i < scrapes[rooto].size(); ++i)
{
g.push({0,{rooto,scrapes[rooto][i]}});
dist[rooto][scrapes[rooto][i]]=0;
}
while(!g.empty())
{
auto u = g.top();
auto tower = u.second.first;
g.pop();
if(dist[tower][u.second.second]<u.first)continue;
for (auto k:scrapes[tower])
{
ll next = tower+k;
ll last = tower-k;
if(last>=0 && dist[last][k]>u.first+1)
{
dist[last][k]=u.first+1;
g.push({u.first+1,{last,k}});
}
if(next<n && dist[next][k]>u.first+1)
{
dist[next][k]=u.first+1;
g.push({u.first+1,{next,k}});
}
}
ll next = tower+u.second.second;
ll last = tower-u.second.second;
if(last>=0 && dist[last][u.second.second]>u.first+1)
{
dist[last][u.second.second]=u.first+1;
g.push({u.first+1,{last,u.second.second}});
}
if(next<n && dist[next][u.second.second]>u.first+1)
{
dist[next][u.second.second]=u.first+1;
g.push({u.first+1,{next,u.second.second}});
}
}
ll ans=INF;
//debugs(rooto,dest);
for (ll i = 0; i < v; ++i)
{
ans=min(ans,dist[dest][i]);
}
if(ans==INF)cout<<-1;
else cout<<ans;
return 0;
}
//code the AC sol !
// BS/queue/map
Compilation message
sculpture.cpp:4:0: warning: ignoring #pragma GCC optimization [-Wunknown-pragmas]
#pragma GCC optimization ("O3")
sculpture.cpp:5:0: warning: ignoring #pragma GCC optimization [-Wunknown-pragmas]
#pragma GCC optimization ("unroll-loops")
sculpture.cpp: In function 'int main()':
sculpture.cpp:35:10: warning: unused variable 'y' [-Wunused-variable]
ll x,y;
^
sculpture.cpp:50:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
for (ll i = 0; i < scrapes[rooto].size(); ++i)
~~^~~~~~~~~~~~~~~~~~~~~~~
sculpture.cpp:32:6: warning: 'rooto' may be used uninitialized in this function [-Wmaybe-uninitialized]
ll rooto,dest;
^~~~~
sculpture.cpp:32:12: warning: 'dest' may be used uninitialized in this function [-Wmaybe-uninitialized]
ll rooto,dest;
^~~~
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
2 ms |
376 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
2 ms |
376 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
2 ms |
376 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
2 ms |
376 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
2 ms |
376 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
