#include <bits/stdc++.h>
#define f first
#define s second
using namespace std;
const int MAXN = 3e4;
const int MAX = 5e5;
vector<pair<int,int>> power[MAXN+1]; //power[i] saves the doges with the power i
int l[MAXN+1], r[MAXN+1]; //do it for the index
vector<int> adj[MAXN+1];
vector<int> q[MAX+1];
int dp[MAXN+1];
int val;
bool cmp(pair<int,int> a, pair<int,int> b){
if(a.f % val != b.f % val) return a.f%val < b.f % val;
return a.f < b.f;
}
int main()
{
ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
int N,M; cin >> N >> M; //number of skyscrapers, number of doges
vector<pair<int,int>> doges(M);
set<pair<int,int>> uni;
for(int i = 0;i<M;++i){
cin >> doges[i].f >> doges[i].s;
if(uni.find({doges[i].f,doges[i].s}) != uni.end()){
continue;
}
uni.insert({doges[i].f,doges[i].s});
power[doges[i].s].push_back({doges[i].f,i}); //save the ones with the same power together -> building and index
adj[doges[i].f].push_back(i);
}
for(int i = 1;i<=MAXN;++i){
if(power[i].size() == 0) continue;
val = i;
sort(power[i].begin(),power[i].end(),cmp);
l[power[i][0].s] = power[i][0].f%i;
for(int j = 0;j<power[i].size()-1;++j){
if(power[i][j].f % i == power[i][j+1].f % i){
r[power[i][j].s] = power[i][j+1].f;
l[power[i][j+1].s] = power[i][j].f;
}
else{
r[power[i][j].s] = N-1;
l[power[i][j+1].s] = power[i][j+1].f%i;
}
}
r[power[i].back().s] = N-1;
}
q[0].push_back(doges[0].f);
fill(dp,dp+N,(1<<30));
for(int i = 0;i<=MAX;++i){
while(!q[i].empty()){
int u = q[i].back(); q[i].pop_back();
if(dp[u] != (1<<30)) continue;
dp[u] = i;
for(auto v : adj[u]){
for(int j = l[v];j <= r[v];j += doges[v].s){
int cur = abs(u-j)/doges[v].s;
if(cur+i < dp[j]){
q[cur+i].push_back(j);
}
}
}
}
}
if(dp[doges[1].f] == (1<<30)){
cout << -1 << "\n";
}
else{
cout << dp[doges[1].f] << "\n";
}
return 0;
}
v
Compilation message
skyscraper.cpp: In function 'int main()':
skyscraper.cpp:37:24: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
37 | for(int j = 0;j<power[i].size()-1;++j){
| ~^~~~~~~~~~~~~~~~~~
skyscraper.cpp: At global scope:
skyscraper.cpp:74:1: error: 'v' does not name a type
74 | v
| ^
