func_code_string: #include <bits/stdc++.h>   using namespace std;   int main() {     int n, k;     cin >> n >> k;     vector<float> coordinates;     for (int i = 0; i < (int)(n); ++i) {       float a, b;       cin >> a >> b;       coordinates.push_back(a);       coordinates.push_back(b);     }     float sum = 0;     std::cout << fixed;     std::cout << setprecision(9);     for (int i = 0; i < coordinates.size() - 2; i += 2) {       sum += sqrt(pow(abs(coordinates[i] - coordinates[i + 2]), 2) +                   pow(abs(coordinates[i + 1] - coordinates[i + 3]), 2)) /              50;     }     cout << sum * k <<   n ;   }   