Problem p03363 (C++)

Buggy submission (status: Time Limit Exceeded):
#include <algorithm>
#include <bitset>
#include <cctype>
#include <cmath>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <ctime>
#include <deque>
#include <functional>
#include <iomanip>
#include <iostream>
#include <list>
#include <map>
#include <numeric>
#include <set>
#include <sstream>
#include <stack>
#include <stdio.h>
#include <string>
#include <utility>
#include <vector>

using namespace std;

// conversion
//------------------------------------------
inline int toInt(string s) {
  int v;
  istringstream sin(s);
  sin >> v;
  return v;
}
template <class T> inline string toString(T x) {
  ostringstream sout;
  sout << x;
  return sout.str();
}

// math
//-------------------------------------------
template <class T> inline T sqr(T x) { return x * x; }

// typedef
//------------------------------------------
typedef vector<int> VI;
typedef vector<VI> VVI;
typedef vector<string> VS;
typedef pair<int, int> PII;
typedef long long LL;

// container util
//------------------------------------------
#define ALL(a) (a).begin(), (a).end()
#define RALL(a) (a).rbegin(), (a).rend()
#define PB push_back
#define MP make_pair
#define SZ(a) int((a).size())
#define EACH(i, c)                                                             \
  for (typeof((c).begin()) i = (c).begin(); i != (c).end(); ++i)
#define EXIST(s, e) ((s).find(e) != (s).end())
#define SORT(c) sort((c).begin(), (c).end())

// repetition
//------------------------------------------
#define FOR(i, a, b) for (int i = (a); i < (b); ++i)
#define REP(i, n) FOR(i, 0, n)

// constant
//--------------------------------------------
const double EPS = 1e-10;
const double PI = acos(-1.0);

// clear memory
#define CLR(a) memset((a), 0, sizeof(a))

// debug
#define dump(x) cerr << #x << " = " << (x) << endl;
#define debug(x)                                                               \
  cerr << #x << " = " << (x) << " (L" << __LINE__ << ")"                       \
       << " " << __FILE__ << endl;
long long combi(long long n, long long k) {
  std::map<std::string, long long> memo;
  if (n == k || k == 0)
    return 1;
  else {
    std::string key = std::to_string(n) + std::to_string(k);
    if (memo.count(key) != 0) {
      return memo[key];
    } else {
      LL out = combi(n - 1, k - 1) + combi(n - 1, k);
      memo[key] = out;
      return out;
    }
  }
}
// pair sort
bool compare_by_b(pair<LL, LL> a, pair<LL, LL> b) {
  if (a.second != b.second) {
    return a.second < b.second;
  } else {
    return a.first < b.first;
  }
}

void solve(long long N, std::vector<long long> A) {
  vector<LL> s;
  LL sum = 0;
  REP(i, N) {
    s.PB(A[i] + sum);
    sum += A[i];
  }
  s.PB(0);
  SORT(s);
  map<LL, LL> m;
  REP(i, s.size()) { m[s[i]] = 0; }

  REP(i, s.size()) { m[s[i]]++; }
  LL ans = 0;
  REP(i, s.size()) {
    if (m[s[i]] >= 2) {
      // ans+=m[s[i]] C 2
      ans += combi(m[s[i]], 2);
      m[s[i]] = 0;
    }
  }
  cout << ans << endl;
}

int main() {
  long long N;
  scanf("%lld", &N);
  std::vector<long long> A(N);
  for (int i = 0; i < N; i++) {
    scanf("%lld", &A[i]);
  }
  solve(N, std::move(A));
  return 0;
}


Fixed submission:
#include <algorithm>
#include <bitset>
#include <cctype>
#include <cmath>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <ctime>
#include <deque>
#include <functional>
#include <iomanip>
#include <iostream>
#include <list>
#include <map>
#include <numeric>
#include <set>
#include <sstream>
#include <stack>
#include <stdio.h>
#include <string>
#include <utility>
#include <vector>

using namespace std;

// conversion
//------------------------------------------
inline int toInt(string s) {
  int v;
  istringstream sin(s);
  sin >> v;
  return v;
}
template <class T> inline string toString(T x) {
  ostringstream sout;
  sout << x;
  return sout.str();
}

// math
//-------------------------------------------
template <class T> inline T sqr(T x) { return x * x; }

// typedef
//------------------------------------------
typedef vector<int> VI;
typedef vector<VI> VVI;
typedef vector<string> VS;
typedef pair<int, int> PII;
typedef long long LL;

// container util
//------------------------------------------
#define ALL(a) (a).begin(), (a).end()
#define RALL(a) (a).rbegin(), (a).rend()
#define PB push_back
#define MP make_pair
#define SZ(a) int((a).size())
#define EACH(i, c)                                                             \
  for (typeof((c).begin()) i = (c).begin(); i != (c).end(); ++i)
#define EXIST(s, e) ((s).find(e) != (s).end())
#define SORT(c) sort((c).begin(), (c).end())

// repetition
//------------------------------------------
#define FOR(i, a, b) for (int i = (a); i < (b); ++i)
#define REP(i, n) FOR(i, 0, n)

// constant
//--------------------------------------------
const double EPS = 1e-10;
const double PI = acos(-1.0);

// clear memory
#define CLR(a) memset((a), 0, sizeof(a))

// debug
#define dump(x) cerr << #x << " = " << (x) << endl;
#define debug(x)                                                               \
  cerr << #x << " = " << (x) << " (L" << __LINE__ << ")"                       \
       << " " << __FILE__ << endl;
long long combi(long long n, long long k) {
  std::map<std::string, long long> memo;
  if (n == k || k == 0)
    return 1;
  else {
    std::string key = std::to_string(n) + std::to_string(k);
    if (memo.count(key) != 0) {
      return memo[key];
    } else {
      LL out = combi(n - 1, k - 1) + combi(n - 1, k);
      memo[key] = out;
      return out;
    }
  }
}
// pair sort
bool compare_by_b(pair<LL, LL> a, pair<LL, LL> b) {
  if (a.second != b.second) {
    return a.second < b.second;
  } else {
    return a.first < b.first;
  }
}

void solve(long long N, std::vector<long long> A) {
  vector<LL> s;
  LL sum = 0;
  REP(i, N) {
    s.PB(A[i] + sum);
    sum += A[i];
  }
  s.PB(0);
  SORT(s);
  map<LL, LL> m;
  REP(i, s.size()) { m[s[i]] = 0; }

  REP(i, s.size()) { m[s[i]]++; }
  LL ans = 0;
  REP(i, s.size()) {
    if (m[s[i]] >= 2) {
      LL num = m[s[i]];
      ans += num * (num - 1) / 2;
      m[s[i]] = 0;
    }
  }
  cout << ans << endl;
}

int main() {
  long long N;
  scanf("%lld", &N);
  std::vector<long long> A(N);
  for (int i = 0; i < N; i++) {
    scanf("%lld", &A[i]);
  }
  solve(N, std::move(A));
  return 0;
}