Problem p03173 (C++)

Buggy submission (status: Time Limit Exceeded):
#define DEBUG 1
#include <algorithm>
#include <cmath>
#include <cstring>
#include <deque>
#include <iomanip>
#include <iostream>
#include <map>
#include <queue>
#include <set>
#include <stack>
#include <string>
#include <tuple>
#include <utility>
#include <vector>
using namespace std;
using ll = long long;
using ull = unsigned long long;
using ld = long double;
using vll = vector<ll>;
using vvll = vector<vll>;
using pll = pair<ll, ll>;
using tll = tuple<ll, ll, ll>;
#define all(v) (v).begin(), (v).end()
#define for1(i, n) for (ll i = 0; i < (n); i++)
#define for2(i, m, n) for (ll i = (m); i < (n); i++)
#define for3(i, m, n, d) for (ll i = (m); i < (n); i += (d))
#define rfor2(i, m, n) for (ll i = (m); i > (n); i--)
#define rfor3(i, m, n, d) for (ll i = (m); i > (n); i += (d))
#define INF 1111111111111111111LL
#define MOD 1000000007LL // 10**9 + 7
#define print(...) print_1(__VA_ARGS__)
#define in(...) in_1(__VA_ARGS__)
#if DEBUG
#define dump(...) dump_1(#__VA_ARGS__, __VA_ARGS__)
#else
#define dump(...)
#endif
template <typename Head> void dump_1(const char *str, Head &&h) {
  cerr << str << ": " << h << '\n';
}
template <typename Head, typename... Tail>
void dump_1(const char *str, Head &&h, Tail &&...t) {
  while (*str != ',') {
    cerr << *str++;
  }
  cerr << ": " << h << ' ';
  dump_1(str + 1, t...);
}
template <typename T1, typename T2>
ostream &operator<<(ostream &os, const pair<T1, T2> &v) {
  os << '(' << v.first << ", " << v.second << ')';
  return os;
}
template <typename T1, typename T2, typename T3>
ostream &operator<<(ostream &os, const tuple<T1, T2, T3> &v) {
  os << '(' << get<0>(v) << ", " << get<1>(v) << ", " << get<2>(v) << ')';
  return os;
}
template <typename T> ostream &operator<<(ostream &os, const vector<T> &v) {
  for (auto it = v.begin(); it != v.end(); it++) {
    if (it != v.begin()) {
      os << ' ';
    }
    os << *it;
  }
  return os;
}
template <typename T> ostream &operator<<(ostream &os, const set<T> &v) {
  for (auto it = v.begin(); it != v.end(); it++) {
    if (it != v.begin()) {
      os << ' ';
    }
    os << *it;
  }
  return os;
}
template <typename T> ostream &operator<<(ostream &os, const multiset<T> &v) {
  for (auto it = v.begin(); it != v.end(); it++) {
    if (it != v.begin()) {
      os << ' ';
    }
    os << *it;
  }
  return os;
}
template <typename T1, typename T2>
ostream &operator<<(ostream &os, const map<T1, T2> &v) {
  os << '{';
  for (auto it = v.begin(); it != v.end(); it++) {
    if (it != v.begin()) {
      os << ", ";
    }
    os << it->first << ':' << it->second;
  }
  os << '}';
  return os;
}
void Yes(void) { cout << "Yes\n"; }
void No(void) { cout << "No\n"; }
void YES(void) { cout << "YES\n"; }
void NO(void) { cout << "NO\n"; }
template <typename T> bool chmax(T &a, const T &b) {
  if (a < b) {
    a = b;
    return true;
  }
  return false;
}
template <typename T> bool chmin(T &a, const T &b) {
  if (a > b) {
    a = b;
    return true;
  }
  return false;
}
template <typename T> void vin(vector<T> &v, ll len) {
  for1(i, len) { cin >> v[i]; }
}
template <typename Head> void in_1(Head &h) { cin >> h; }
template <typename Head, typename... Tail> void in_1(Head &h, Tail &...t) {
  cin >> h;
  in_1(t...);
}
template <typename Head> void print_1(Head &&h) { cout << h << '\n'; }
template <typename Head, typename... Tail> void print_1(Head &&h, Tail &&...t) {
  cout << h << ' ';
  print_1(t...);
}
//---------------------------------------------------------
ll memo[400][400];
ll A[400];
ll C[401];
ll calc(ll l, ll r) {
  if (memo[l][r] != 0) {
    return memo[l][r];
  }
  if (l == r) {
    return 0;
  }
  ll ret = INF;
  for2(i, l, r) {
    ll ret1 = calc(l, i) + calc(i + 1, r) + C[r + 1] - C[l];
    chmin(ret, ret1);
  }
  return ret;
}

void solve() {
  ll N;
  in(N);
  for1(i, N) { in(A[i]); }
  for1(i, N) { C[i + 1] = C[i] + A[i]; }
  print(calc(0, N - 1));
}
int main() {
  ios::sync_with_stdio(false);
  cin.tie(0);
  cout << fixed << setprecision(16);
  cerr << fixed << setprecision(16);
  solve();
}


Fixed submission:
#define DEBUG 1
#include <algorithm>
#include <cmath>
#include <cstring>
#include <deque>
#include <iomanip>
#include <iostream>
#include <map>
#include <queue>
#include <set>
#include <stack>
#include <string>
#include <tuple>
#include <utility>
#include <vector>
using namespace std;
using ll = long long;
using ull = unsigned long long;
using ld = long double;
using vll = vector<ll>;
using vvll = vector<vll>;
using pll = pair<ll, ll>;
using tll = tuple<ll, ll, ll>;
#define all(v) (v).begin(), (v).end()
#define for1(i, n) for (ll i = 0; i < (n); i++)
#define for2(i, m, n) for (ll i = (m); i < (n); i++)
#define for3(i, m, n, d) for (ll i = (m); i < (n); i += (d))
#define rfor2(i, m, n) for (ll i = (m); i > (n); i--)
#define rfor3(i, m, n, d) for (ll i = (m); i > (n); i += (d))
#define INF 1111111111111111111LL
#define MOD 1000000007LL // 10**9 + 7
#define print(...) print_1(__VA_ARGS__)
#define in(...) in_1(__VA_ARGS__)
#if DEBUG
#define dump(...) dump_1(#__VA_ARGS__, __VA_ARGS__)
#else
#define dump(...)
#endif
template <typename Head> void dump_1(const char *str, Head &&h) {
  cerr << str << ": " << h << '\n';
}
template <typename Head, typename... Tail>
void dump_1(const char *str, Head &&h, Tail &&...t) {
  while (*str != ',') {
    cerr << *str++;
  }
  cerr << ": " << h << ' ';
  dump_1(str + 1, t...);
}
template <typename T1, typename T2>
ostream &operator<<(ostream &os, const pair<T1, T2> &v) {
  os << '(' << v.first << ", " << v.second << ')';
  return os;
}
template <typename T1, typename T2, typename T3>
ostream &operator<<(ostream &os, const tuple<T1, T2, T3> &v) {
  os << '(' << get<0>(v) << ", " << get<1>(v) << ", " << get<2>(v) << ')';
  return os;
}
template <typename T> ostream &operator<<(ostream &os, const vector<T> &v) {
  for (auto it = v.begin(); it != v.end(); it++) {
    if (it != v.begin()) {
      os << ' ';
    }
    os << *it;
  }
  return os;
}
template <typename T> ostream &operator<<(ostream &os, const set<T> &v) {
  for (auto it = v.begin(); it != v.end(); it++) {
    if (it != v.begin()) {
      os << ' ';
    }
    os << *it;
  }
  return os;
}
template <typename T> ostream &operator<<(ostream &os, const multiset<T> &v) {
  for (auto it = v.begin(); it != v.end(); it++) {
    if (it != v.begin()) {
      os << ' ';
    }
    os << *it;
  }
  return os;
}
template <typename T1, typename T2>
ostream &operator<<(ostream &os, const map<T1, T2> &v) {
  os << '{';
  for (auto it = v.begin(); it != v.end(); it++) {
    if (it != v.begin()) {
      os << ", ";
    }
    os << it->first << ':' << it->second;
  }
  os << '}';
  return os;
}
void Yes(void) { cout << "Yes\n"; }
void No(void) { cout << "No\n"; }
void YES(void) { cout << "YES\n"; }
void NO(void) { cout << "NO\n"; }
template <typename T> bool chmax(T &a, const T &b) {
  if (a < b) {
    a = b;
    return true;
  }
  return false;
}
template <typename T> bool chmin(T &a, const T &b) {
  if (a > b) {
    a = b;
    return true;
  }
  return false;
}
template <typename T> void vin(vector<T> &v, ll len) {
  for1(i, len) { cin >> v[i]; }
}
template <typename Head> void in_1(Head &h) { cin >> h; }
template <typename Head, typename... Tail> void in_1(Head &h, Tail &...t) {
  cin >> h;
  in_1(t...);
}
template <typename Head> void print_1(Head &&h) { cout << h << '\n'; }
template <typename Head, typename... Tail> void print_1(Head &&h, Tail &&...t) {
  cout << h << ' ';
  print_1(t...);
}
//---------------------------------------------------------
ll memo[400][400];
ll A[400];
ll C[401];
ll calc(ll l, ll r) {
  if (memo[l][r] != 0) {
    return memo[l][r];
  }
  if (l == r) {
    return 0;
  }
  ll ret = INF;
  for2(i, l, r) {
    ll ret1 = calc(l, i) + calc(i + 1, r) + C[r + 1] - C[l];
    chmin(ret, ret1);
  }
  memo[l][r] = ret;
  return ret;
}

void solve() {
  ll N;
  in(N);
  for1(i, N) { in(A[i]); }
  for1(i, N) { C[i + 1] = C[i] + A[i]; }
  print(calc(0, N - 1));
}
int main() {
  ios::sync_with_stdio(false);
  cin.tie(0);
  cout << fixed << setprecision(16);
  cerr << fixed << setprecision(16);
  solve();
}