func_code_string: #include <bits/stdc++.h>   typedef long long ll;   typedef long double ld;   using namespace std;   vector<ll> prime_factors(ll num) {     vector<ll> ans;     while (num % 2) {       ans.push_back(2);       num /= 2;     }     for (int i = 3; i * i <= num; i += 2) {       while (num % i == 0) {         ans.push_back(i);         num /= i;       }     }     if (num > 2) ans.push_back(num);     return ans;   }   void tests() {     int n;     cin >> n;     map<int, vector<int>> data;     vector<pair<int, int>> ans;     ans.reserve(n);     for (int i = 1; i < n + 1; i++) {       int x;       cin >> x;       data[x].push_back(i);     }     for (auto &i : data) {       int len = i.second.size();       if (len == 1)         ans.push_back(make_pair(i.first, 0));       else if (len == 2)         ans.push_back(make_pair(i.first, i.second[1] - i.second[0]));       else {         int cd = i.second[1] - i.second[0];         for (int pos = 2; pos < len; ++pos) {           if (i.second[pos] - i.second[pos - 1] != cd) goto end;         }         ans.push_back(make_pair(i.first, cd));       }     end:;     }     cout << ans.size() << char(10);     for (auto &i : ans) cout << i.first << char(32) << i.second << char(10);   }   int32_t main() {     ios_base::sync_with_stdio(false);     cin.tie(NULL);     int t = 1;     while (t--) {       tests();     }     return 0;   }   