Problem p00522 (C++) — buggy submission, verdict: Time Limit Exceeded

#include <algorithm>
#include <cassert>
#include <cctype>
#include <cmath>
#include <complex>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <deque>
#include <functional>
#include <iomanip>
#include <iostream>
#include <iterator>
#include <list>
#include <map>
#include <numeric>
#include <queue>
#include <set>
#include <sstream>
#include <stack>
#include <string>
#include <vector>

#define REP(i, m, n) for (int i = m; i < n; i++)
#define rep(i, n) for (int i = 0; i < n; i++)
#define rp(i, c) rep(i, (int)c.size())
#define fr(i, c)                                                               \\
  for (__typeof((c).begin()) i = (c).begin(); i != (c).end(); i++)
#define mp make_pair
#define pb push_back
#define all(c) (c).begin(), (c).end()
#define rall(u) (u).rbegin(), (u).rend()
#define dbg(x) cerr << #x << " = " << (x) << endl
#define v_delete(a, b) (a).erase(remove((a).begin(), (a).end(), b), (a).end())
#define v_unique(a) (a).erase(unique((a).begin(), (a).end()), (a).end())
#define VV(T) vector<vector<T>>
#define init(a, b) memset((a), (b), sizeof((a)))
using namespace std;

typedef long long ll;
typedef vector<int> vi;
typedef pair<int, int> pi;
const int inf = 1 << 28;
const double INF = 1e10, EPS = 1e-9;

template <class T> int SIZE(T a) { return a.size(); }
template <class T> string IntToString(T num) {
  string res;
  stringstream ss;
  ss << num;
  return ss.str();
}
template <class T> T StringToInt(string str) {
  T res = 0;
  for (int i = 0; i < SIZE(str); i++)
    res = (res * 10 + str[i] - '0');
  return res;
}
template <class T> T gcd(T a, T b) {
  if (b == 0)
    return a;
  return gcd(b, a % b);
}
template <class T> T lcm(T a, T b) { return a / gcd(a, b) * b; }

template <class T> void input(T &a, int n) {
  for (int i = 0; i < n; ++i)
    cin >> a[i];
}
template <class T> void input(T *a, int n) {
  for (int i = 0; i < n; ++i)
    cin >> a[i];
}
typedef pair<int, int> pii;

int M, N;

int P[10000 + 10];
int C[500 + 10];
int E[500 + 10];
int Pt[10000 + 10];

int dp[500 + 10][10000 + 10];

int main() {

  cin >> M >> N;
  rep(i, M) { cin >> P[i]; }
  rep(i, N) { cin >> C[i] >> E[i]; }
  sort(P, P + M, greater<int>());

  for (int i = 1; i <= M; i++) {
    Pt[i] = Pt[i - 1] + P[i - 1];
  }
  for (int i = 0; i <= N; i++) {
    for (int j = 0; j <= M; j++) {
      dp[i][j] = -inf;
    }
  }
  dp[0][0] = 0;

  for (int i = 1; i <= N; i++) {
    for (int j = 0; j <= M; j++) {
      dp[i][j] = max(dp[i - 1][j], dp[i][j]);
      if (j - C[i - 1] > 0) {
        dp[i][j] =
            max(dp[i - 1][j - C[i - 1]] + Pt[j] - Pt[j - C[i - 1]] - E[i - 1],
                dp[i][j]);
      } else {
        dp[i][j] = max(dp[i - 1][0] + Pt[j] - E[i - 1], dp[i][j]);
      }
      if (dp[i][j] < 0)
        dp[i][j] = -inf;
    }
  }

  cout << *max_element(dp[N], dp[N] + M + 1) << endl;
}

Error: TLE

Fixed submission:

#include <algorithm>
#include <cassert>
#include <cctype>
#include <cmath>
#include <complex>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <deque>
#include <functional>
#include <iomanip>
#include <iostream>
#include <iterator>
#include <list>
#include <map>
#include <numeric>
#include <queue>
#include <set>
#include <sstream>
#include <stack>
#include <string>
#include <vector>

#define REP(i, m, n) for (int i = m; i < n; i++)
#define rep(i, n) for (int i = 0; i < n; i++)
#define rp(i, c) rep(i, (int)c.size())
#define fr(i, c)                                                               \\
  for (__typeof((c).begin()) i = (c).begin(); i != (c).end(); i++)
#define mp make_pair
#define pb push_back
#define all(c) (c).begin(), (c).end()
#define rall(u) (u).rbegin(), (u).rend()
#define dbg(x) cerr << #x << " = " << (x) << endl
#define v_delete(a, b) (a).erase(remove((a).begin(), (a).end(), b), (a).end())
#define v_unique(a) (a).erase(unique((a).begin(), (a).end()), (a).end())
#define VV(T) vector<vector<T>>
#define init(a, b) memset((a), (b), sizeof((a)))
using namespace std;

typedef long long ll;
typedef vector<int> vi;
typedef pair<int, int> pi;
const int inf = 1 << 28;
const double INF = 1e10, EPS = 1e-9;

template <class T> int SIZE(T a) { return a.size(); }
template <class T> string IntToString(T num) {
  string res;
  stringstream ss;
  ss << num;
  return ss.str();
}
template <class T> T StringToInt(string str) {
  T res = 0;
  for (int i = 0; i < SIZE(str); i++)
    res = (res * 10 + str[i] - '0');
  return res;
}
template <class T> T gcd(T a, T b) {
  if (b == 0)
    return a;
  return gcd(b, a % b);
}
template <class T> T lcm(T a, T b) { return a / gcd(a, b) * b; }

template <class T> void input(T &a, int n) {
  for (int i = 0; i < n; ++i)
    cin >> a[i];
}
template <class T> void input(T *a, int n) {
  for (int i = 0; i < n; ++i)
    cin >> a[i];
}
typedef pair<int, int> pii;

int M, N;

int P[10000 + 10];
int C[500 + 10];
int E[500 + 10];
int Pt[10000 + 10];

int dp[500 + 10][10000 + 10];

int main() {

  cin >> M >> N;
  rep(i, M) { cin >> P[i]; }
  rep(i, N) { cin >> C[i] >> E[i]; }
  sort(P, P + M, greater<int>());

  for (int i = 1; i <= M; i++) {
    Pt[i] = Pt[i - 1] + P[i - 1];
  }

  for (int i = 1; i <= N; i++) {
    for (int j = 0; j <= M; j++) {
      for (int k = 1; k <= C[i - 1] && j - k >= 0; k++) {
        dp[i][j] =
            max(dp[i - 1][j - k] + Pt[j] - Pt[j - k] - E[i - 1], dp[i][j]);
      }
      dp[i][j] = max(dp[i - 1][j], dp[i][j]);
    }
  }

  cout << *max_element(dp[N], dp[N] + M + 1) << endl;
}