func_code_string: #include <bits/stdc++.h>   using namespace std;   int n, m;   vector<int> v;   set<int> g[100005];   vector<pair<int, int> > f;   int main() {     ios::sync_with_stdio(false);     cin >> n >> m;     for (int i = 1; i * i <= n; i++) {       if (n % i == 0) {         v.push_back(i);         if (i * i != n && i != 1) v.push_back(n / i);       }     }     int a, b;     for (int i = 1; i <= m; i++) {       cin >> a >> b;       g[a].insert(a);       g[b].insert(a);       f.push_back(make_pair(a, b));     }     for (auto x : v) {       bool flag = 1;       for (auto y : f) {         int l = y.first, r = y.second;         l += x, r += x;         if (l > n) l -= n;         if (r > n) r -= n;         if (g[l].count(r) || g[r].count(l))           continue;         else {           flag = 0;           break;         }       }       if (flag) {         cout <<  Yes  << endl;         exit(0);       }     }     cout <<  No ;   }   