Create tourists.cpp

Author: AymanSalah96

KATTIS/tourists.cpp

@@ -0,0 +1,130 @@
+#include <cstring>
+#include <map>
+#include <deque>
+#include <queue>
+#include <stack>
+#include <sstream>
+#include <numeric>
+#include <iostream>
+#include <iomanip>
+#include <cstdio>
+#include <cmath>
+#include <fstream>
+#include <string>
+#include <cstdlib>
+#include <ctime>
+#include <functional>
+#include <algorithm>
+#include <vector>
+#include <set>
+#include <complex>
+#include <list>
+#include <climits>
+#include <cctype>
+#include <bitset>
+#include <assert.h>
+using namespace std;
+
+#define PI 3.14159265359
+#define all(v) v.begin(),v.end()
+#define sortva(v) sort(all(v))
+#define sortvd(v) sort(v.rbegin(),v.rend())
+#define sortaa(first,n) sort(first,first+n)
+#define sortad(first,n) sort(first,first+n),reverse(first,first+n)
+#define sfi1(v) scanf("%dist",&v)
+#define sfi2(v1,v2) scanf("%dist %dist",&v1,&v2)
+#define sfi3(v1,v2,v3) scanf("%dist %dist %dist",&v1,&v2,&v3)
+#define sfll1(v) scanf("%I64d",&v);
+#define sfll2(v1,v2) scanf("%I64d %I64d",&v1,&v2)
+#define sfll3(v1,v2,v3) scanf("%I64d %I64d %I64d",&v1,&v2,&v3)
+#define sfstr(v) scanf("%sum", v);
+#define sz(v) (int)v.size()
+#define ndl puts("")
+#define flush fflush(stdout)
+#define SS stringstream
+typedef long long ll;
+typedef unsigned long long ull;
+typedef long double ld;
+
+int dx[] = { 0, 0, 1, -1, 1, -1, 1, -1 };
+int dy[] = { 1, -1, 0, 0, -1, 1, 1, -1 };
+
+ll gcd(ll first, ll second) { return !second ? first : gcd(second, first % second); }
+ll lcm(ll first, ll second) { return (first / gcd(first, second)) * second; }
+
+void PLAY() {
+cout << fixed << setprecision(15);
+ios::sync_with_stdio(0);
+cin.tie(0);
+cout.tie(0);
+}
+
+const int MAX = 2e5 + 10;
+const int MAXLOG = 20;
+
+vector<int> adj[MAX]; 
+int table[MAX][MAXLOG], depth[MAX];
+
+void dfs(int u, int p) {
+table[u][0] = p;
+for (int i = 0; i < sz(adj[u]); i++) {
+int v = adj[u][i];
+if (v == p) continue;
+depth[v] = depth[u] + 1;
+dfs(v, u);
+}
+}
+
+int LCA(int u, int v) {
+if (depth[u] < depth[v])
+swap(u, v);
+for (int k = MAXLOG - 1; k >= 0; k--)
+if (depth[u] - (1 << k) >= depth[v])
+u = table[u][k];
+if (u == v) return u;
+for (int k = MAXLOG- 1; k >= 0; k--) {
+if (table[u][k] != table[v][k]) {
+u = table[u][k];
+v = table[v][k];
+}
+}
+return table[u][0];
+}
+
+int length(int u, int v) {
+return depth[u] + depth[v] - 2 * depth[LCA(u, v)];
+}
+
+int main() {
+PLAY();
+
+int n;
+cin >> n;
+for (int i = 1; i < n; i++) {
+int u, v;
+cin >> u >> v;
+u--; v--;
+adj[u].push_back(v);
+adj[v].push_back(u);
+}
+
+memset(table, -1, sizeof table);
+dfs(0, -1);
+
+for (int k = 1; k < MAXLOG; k++) {
+for (int u = 0; u < n; u++) {
+if (table[u][k - 1] == -1) continue;
+table[u][k] = table[table[u][k - 1]][k - 1];
+}
+}
+
+
+ll res = 0;
+for (int i = 1; i <= n; i++)
+for (int j = 2 * i; j <= n; j += i)
+res += length(i - 1, j - 1) + 1;
+
+cout << res << endl;
+
+return 0;
+}