func_code_string: #include <bits/stdc++.h>   using namespace std;   int n, k, x[105], y[105];   double s;   int main(void) {     cin >> n >> k;     for (int i = 0; i < n; i++) cin >> x[i] >> y[i];     int j = 1;     while (j < n) {       s += sqrt((double)(y[j] - y[j - 1]) * (y[j] - y[j - 1]) +                 (double)(x[j] - x[j - 1]) * (x[j] - x[j - 1]));       j++;     }     printf( %0.7f , s * k * 0.02);     return 0;   }   