func_code_string: #include <bits/stdc++.h>   using namespace std;   template <class T>   struct rge {     T b, e;   };   template <class T>   rge<T> range(T i, T j) {     return rge<T>{i, j};   };   template <class A, class B>   ostream &operator<<(ostream &os, pair<A, B> p) {     return os <<  (  << p.first <<  ,   << p.second <<  ) ;   }   template <class T>   ostream &operator<<(ostream &os, rge<T> d) {     os <<  [ ;     for (auto it = d.b; it != d.e; it++) os << (it == d.b ?    :  ,  ) << *it;     return os <<  ] ;   }   const int N = 1e5 + 5;   const long long inf = 1e18;   long long stones[N], frogs[N];   int n, jump;   bool can(long long x) {     for (int i = (1); i <= ((n)); i += (+1)) {       frogs[i] = 0;     }     frogs[0] = x;     int l = 0, r = 1;     while (l < n) {       while (frogs[l] > 0) {         while (r <= n && stones[r] - frogs[r] <= 0) {           r++;         }         if (l + jump < r) {           return false;         }         long long add = min(frogs[l], stones[r] - frogs[r]);         frogs[r] += add;         frogs[l] -= add;       }       l++;       r = max(l + 1, r);     }     return true;   }   int main() {     ios_base::sync_with_stdio(0), cin.tie(0), cout.tie(0), cout.precision(15);     cin >> n >> jump;     for (int i = (1); i <= ((n - 1)); i += (+1)) {       cin >> stones[i];     }     stones[n] = inf;     long long lo = 0, hi = inf;     while (lo + 1 < hi) {       long long mid = (lo + hi) / 2;       if (can(mid)) {         lo = mid;       } else {         hi = mid;       }     }     while (can(lo + 1)) {       lo++;     }     cout << lo <<   n ;     return 0;   }   