#include <bits/stdc++.h>
using namespace std;
const int N = 30010, M = 30010;
int n, m, b[M], p[M], dist[N];
bool mark[N];
vector<int> vec[N];
int main(){
cin >> n >> m;
for (int i = 0; i < m; i ++){
cin >> b[i] >> p[i];
vec[b[i]].push_back(p[i]);
}
for (int i = 0; i < n; i ++){
sort(vec[i].begin(), vec[i].end());
vec[i].resize(unique(vec[i].begin(), vec[i].end()) - vec[i].begin());
}
memset(dist, 63, sizeof dist);
dist[b[0]] = 0;
for (int ii = 0; ii < n; ii ++){
int v = -1;
for (int j = 0; j < n; j ++)
if (!mark[j] and (v == -1 or dist[v] > dist[j]))
v = j;
if (v == b[1]) break;
mark[v] = 1;
for (int d : vec[v]){
if (!exist[v][d]) continue;
for (int i = 1; v + d * i < n; i ++)
dist[v + d * i] = min(dist[v + d * i], dist[v] + i);
for (int i = 1; v - d * i >= 0; i ++)
dist[v - d * i] = min(dist[v - d * i], dist[v] + i);
}
}
if (dist[b[1]] > 1e9)
dist[b[1]] = -1;
cout << dist[b[1]] << endl;
}
Compilation message
skyscraper.cpp: In function 'int main()':
skyscraper.cpp:34:18: error: 'exist' was not declared in this scope; did you mean 'exit'?
34 | if (!exist[v][d]) continue;
| ^~~~~
| exit