LibreOJ/2887/2887.cpp

@@ -1,94 +0,0 @@
-#include <iostream>
-#include <bitset>
-#include <cmath>
-#include <cstring>
-#include <queue>
-#include <vector>
-
-using std::cin;
-using std::cout;
-const char endl = '\n';
-
-const int N = 30001;
-
-int n, m, l, s, t;
-std::vector<std::pair<int, short>> g[N * 101];
-int dist[N * 101];
-std::bitset<N * 101> vis;
-
-int spfa() {
-    memset(dist, 0x3f, sizeof(dist));
-    std::queue<int> q;
-
-    dist[s] = 0;
-    q.push(s);
-    vis[s] = true;
-
-    while (!q.empty()) {
-        int u = q.front();
-        q.pop();
-
-        vis[u] = false;
-
-        for (auto t : g[u]) {
-            int v = t.first;
-            short w = t.second;
-
-            if (dist[v] > dist[u] + w) {
-                dist[v] = dist[u] + w;
-
-                if (!vis[v]) {
-                    q.push(v);
-                    vis[v] = true;
-                }
-            }
-        }
-    }
-
-    return dist[t] == 0x3f3f3f3f ? -1 : dist[t];
-}
-
-int main() {
-    std::ios::sync_with_stdio(false);
-    cin.tie(nullptr);
-
-    cin >> n >> m;
-
-    l = std::min(static_cast<int>(std::sqrt(n)), 100);
-
-    for (int i = 1, b, p; i <= m; i++) {
-        cin >> b >> p;
-
-        b++;
-
-        if (i == 1) s = b;
-        if (i == 2) t = b;
-
-        if (p <= l) {
-            g[b].emplace_back(p * n + b, 0);
-        } else {
-            for (int j = 1; b + j * p <= n; j++) {
-                g[b].emplace_back(b + j * p, j);
-            }
-
-            for (int j = 1; b - j * p > 0; j++) {
-                g[b].emplace_back(b - j * p, j);
-            }
-        }
-    }
-
-    for (int i = 1; i <= l; i++) {
-        for (int j = 1; j <= n; j++) {
-            g[i * n + j].emplace_back(j, 0);
-        }
-
-        for (int j = 1; j <= n - i; j++) {
-            g[i * n + j].emplace_back(i * n + j + i, 1);
-            g[i * n + j + i].emplace_back(i * n + j, 1);
-        }
-    }
-
-    cout << spfa() << endl;
-
-    return 0;
-}