Problem p03173 (C++)

Buggy submission (status: Time Limit Exceeded):
#include <algorithm>
#include <bitset>
#include <ciso646>
#include <cmath>
#include <complex>
#include <cstdio>
#include <functional>
#include <iomanip>
#include <iostream>
#include <map>
#include <queue>
#include <random>
#include <set>
#include <stack>
#include <string>
#include <unordered_map>
#include <vector>
using namespace std;
typedef long long ll;
typedef unsigned int ui;
const ll mod = 1000000007;
const ll INF = (ll)1000000007 * 1000000007;
typedef pair<int, int> P;
#define stop                                                                   \
  char nyaa;                                                                   \
  cin >> nyaa;
#define rep(i, n) for (int i = 0; i < n; i++)
#define per(i, n) for (int i = n - 1; i >= 0; i--)
#define Rep(i, sta, n) for (int i = sta; i < n; i++)
#define rep1(i, n) for (int i = 1; i <= n; i++)
#define per1(i, n) for (int i = n; i >= 1; i--)
#define Rep1(i, sta, n) for (int i = sta; i <= n; i++)
typedef long double ld;
typedef complex<ld> Point;
const ld eps = 1e-3;
const ld pi = acos(-1.0);
typedef pair<ll, ll> LP;
typedef pair<ld, ld> LDP;
int n;
ll a[400];
ll s[401];
bool chked[400][400];
ll ans[400][400];
ll dfs(int le, int ri) {
  if (le == ri)
    return 0;
  if (chked[le][ri])
    return ans[le][ri];
  chked[le][ri] - true;
  ll res = INF;
  Rep(i, le, ri) {
    ll sum = dfs(le, i) + dfs(i + 1, ri);
    res = min(res, sum);
  }
  res += s[ri + 1] - s[le];
  return ans[le][ri] = res;
}

int main() {
  cin >> n;
  rep(i, n) cin >> a[i];
  s[0] = 0;
  rep(i, n) s[i + 1] = s[i] + a[i];
  cout << dfs(0, n - 1) << endl;
  // stop
  return 0;
}

Fixed submission:
#include <algorithm>
#include <bitset>
#include <ciso646>
#include <cmath>
#include <complex>
#include <cstdio>
#include <functional>
#include <iomanip>
#include <iostream>
#include <map>
#include <queue>
#include <random>
#include <set>
#include <stack>
#include <string>
#include <unordered_map>
#include <vector>
using namespace std;
typedef long long ll;
typedef unsigned int ui;
const ll mod = 1000000007;
const ll INF = (ll)1000000007 * 1000000007;
typedef pair<int, int> P;
#define stop                                                                   \
  char nyaa;                                                                   \
  cin >> nyaa;
#define rep(i, n) for (int i = 0; i < n; i++)
#define per(i, n) for (int i = n - 1; i >= 0; i--)
#define Rep(i, sta, n) for (int i = sta; i < n; i++)
#define rep1(i, n) for (int i = 1; i <= n; i++)
#define per1(i, n) for (int i = n; i >= 1; i--)
#define Rep1(i, sta, n) for (int i = sta; i <= n; i++)
typedef long double ld;
typedef complex<ld> Point;
const ld eps = 1e-3;
const ld pi = acos(-1.0);
typedef pair<ll, ll> LP;
typedef pair<ld, ld> LDP;
int n;
ll a[400];
ll s[401];
bool chked[400][400];
ll ans[400][400];
ll dfs(int le, int ri) {
  if (le == ri)
    return 0;
  if (chked[le][ri])
    return ans[le][ri];
  chked[le][ri] = true;
  ll res = INF;
  Rep(i, le, ri) {
    ll sum = dfs(le, i) + dfs(i + 1, ri);
    res = min(res, sum);
  }
  res += s[ri + 1] - s[le];
  return ans[le][ri] = res;
}

int main() {
  cin >> n;
  rep(i, n) cin >> a[i];
  s[0] = 0;
  rep(i, n) s[i + 1] = s[i] + a[i];
  cout << dfs(0, n - 1) << endl;
  // stop
  return 0;
}