Problem p02647 (C++) — buggy submission, verdict: Time Limit Exceeded

#pragma GCC optimize("O3")
#include <algorithm>
#include <bitset>
#include <cctype>
#include <cmath>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <ctime>
#include <deque>
#include <iomanip>
#include <iostream>
#include <istream>
#include <iterator>
#include <list>
#include <map>
#include <numeric>
#include <ostream>
#include <queue>
#include <set>
#include <sstream>
#include <stack>
#include <string>
#include <unordered_map>
#include <utility>
#include <vector>
#define IINF 1000000000
#define INF 9223372036854775807
#define MOD 998244353
#define mod 1000000007
#define INT_MAX_ 2147483647
#define EPS (1e-10)
#define REP(i, a, n) fo - r(ll i = a; i < (ll)(n); i++)
#define REPE(i, a, n) for (ll i = a; i <= (ll)(n); i++)
#define rep(i, n) for (ll i = 0; i < (ll)(n); i++)
#define rep1(i, n) for (int i = 1; i <= (int)(n); i++)
#define Endl endl
#define fi first
#define se second
#define pb push_back
#define mp make_pair
#define mt make_tuple
#define eb emplace_back
#define mmax(x, y) (x > y ? x : y)
#define mmin(x, y) (x < y ? x : y)
#define chmax(x, y) x = mmax(x, y)
#define chmin(x, y) x = mmin(x, y)
#define all(x) (x).begin(), (x).end()
#define siz(x) (ll)(x).size()
#define PI acos(-1.0)
#define me memset
#define bit(n, k) ((n >> k) & 1)
using namespace std;
typedef long long int ll;
typedef unsigned long long int ull;
typedef long double ld;
typedef pair<int, int> Pin;
typedef pair<ll, ll> Pll;
template <class T> using V = vector<T>;
template <typename T>
using min_priority_queue = priority_queue<T, vector<T>, greater<T>>;
long long GCD(long long a, long long b) { return b ? GCD(b, a % b) : a; }
long long LCM(long long a, long long b) { return a / GCD(a, b) * b; }
int dx[4] = {-1, 0, 1, 0};
int dy[4] = {0, -1, 0, 1};
int ddx[8] = {-1, 0, 1, 0, 1, 1, -1, -1};
int ddy[8] = {0, -1, 0, 1, 1, -1, 1, -1};
ll cmp1(pair<ll, ll> a, pair<ll, ll> b) {
  if (a.se != b.se)
    return a.se < b.se;
  else
    return a.fi > b.fi;
}
//----------------------------------------------------------------------
ll sum[200020];
//----------------------------------------------------------------------
int main() {
  cin.tie(0);
  ios::sync_with_stdio(false);
  //-------------------------------
  // ll begin_t=clock();
  // freopen("input.txt", "r", stdin);
  // freopen("output.txt", "w", stdout);
  //-------------------------------
  ll n, k;
  cin >> n >> k;
  V<ll> a(n);
  for (ll i = 0; i < n; i++)
    cin >> a[i];

  for (ll z = 0; z < mmin(k, 41); z++) {
    me(sum, 0, sizeof(sum));
    for (ll i = 0; i < n; i++) {
      sum[mmax(0, i - a[i])]++;
      if (mmin(n - 1, i + a[i]) + 1 < n)
        sum[mmin(n - 1, i + a[i]) + 1]--;
    }
    for (ll i = 1; i < n; i++) {
      sum[i] += sum[i - 1];
    }
    for (ll i = 0; i < n; i++)
      a[i] = sum[i];
  }
  for (ll i = 0; i < n; i++)
    cout << a[i] << " ";
  cout << endl;
  //-------------------------------
  // fclose(stdin);
  // fclose(stdout);
  // ll end_t=clock();cout<<"time="<<end_t-begin_t<<"ms"<<endl;
  //-------------------------------
  return 0;
}
//----------------------------------------------------------------------


Error: TLE

Fixed submission:

#pragma GCC optimize("O3")
#include <algorithm>
#include <bitset>
#include <cctype>
#include <cmath>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <ctime>
#include <deque>
#include <iomanip>
#include <iostream>
#include <istream>
#include <iterator>
#include <list>
#include <map>
#include <numeric>
#include <ostream>
#include <queue>
#include <set>
#include <sstream>
#include <stack>
#include <string>
#include <unordered_map>
#include <utility>
#include <vector>
#define IINF 1000000000
#define INF 9223372036854775807
#define MOD 998244353
#define mod 1000000007
#define INT_MAX_ 2147483647
#define EPS (1e-10)
#define REP(i, a, n) fo - r(ll i = a; i < (ll)(n); i++)
#define REPE(i, a, n) for (ll i = a; i <= (ll)(n); i++)
#define rep(i, n) for (ll i = 0; i < (ll)(n); i++)
#define rep1(i, n) for (int i = 1; i <= (int)(n); i++)
#define Endl endl
#define fi first
#define se second
#define pb push_back
#define mp make_pair
#define mt make_tuple
#define eb emplace_back
#define mmax(x, y) (x > y ? x : y)
#define mmin(x, y) (x < y ? x : y)
#define chmax(x, y) x = mmax(x, y)
#define chmin(x, y) x = mmin(x, y)
#define all(x) (x).begin(), (x).end()
#define siz(x) (ll)(x).size()
#define PI acos(-1.0)
#define me memset
#define bit(n, k) ((n >> k) & 1)
using namespace std;
typedef long long int ll;
typedef unsigned long long int ull;
typedef long double ld;
typedef pair<int, int> Pin;
typedef pair<ll, ll> Pll;
template <class T> using V = vector<T>;
template <typename T>
using min_priority_queue = priority_queue<T, vector<T>, greater<T>>;
long long GCD(long long a, long long b) { return b ? GCD(b, a % b) : a; }
long long LCM(long long a, long long b) { return a / GCD(a, b) * b; }
int dx[4] = {-1, 0, 1, 0};
int dy[4] = {0, -1, 0, 1};
int ddx[8] = {-1, 0, 1, 0, 1, 1, -1, -1};
int ddy[8] = {0, -1, 0, 1, 1, -1, 1, -1};
ll cmp1(pair<ll, ll> a, pair<ll, ll> b) {
  if (a.se != b.se)
    return a.se < b.se;
  else
    return a.fi > b.fi;
}
//----------------------------------------------------------------------

//----------------------------------------------------------------------
int main() {
  cin.tie(0);
  ios::sync_with_stdio(false);
  //-------------------------------
  // ll begin_t=clock();
  // freopen("input.txt", "r", stdin);
  // freopen("output.txt", "w", stdout);
  //-------------------------------
  ll n, k;
  cin >> n >> k;
  V<ll> a(n);
  for (ll i = 0; i < n; i++)
    cin >> a[i];

  if (k >= n) {
    for (ll i = 0; i < n; i++)
      cout << n << " ";
    cout << endl;
    return 0;
  }
  V<ll> b(n);
  for (ll i = 0; i < k; i++) {
    ll sum = 0;
    for (ll j = 0; j < n; j++)
      b[j] = a[j];
    for (ll j = 0; j < n; j++) {
      ll cnt = 0;
      for (ll m = 0; m < n; m++) {
        if (b[m] >= abs(m - j)) {
          cnt++;
        }
      }
      a[j] = cnt;
      sum += cnt;
    }
    if (sum == n * n)
      break;
    // for(ll i=0;i<n;i++)cout<<a[i]<<" ";cout<<endl;
  }
  for (ll i = 0; i < n; i++)
    cout << a[i] << " ";
  cout << endl;
  //-------------------------------
  // fclose(stdin);
  // fclose(stdout);
  // ll end_t=clock();cout<<"time="<<end_t-begin_t<<"ms"<<endl;
  //-------------------------------
  return 0;
}
//----------------------------------------------------------------------