#include <bits/stdc++.h>
using namespace std;
const long long int INF = 9223372036854775807;
const long long int mod = 998244353;
vector<int> prime(100001, 1);
void sieve() {
  for (int i = 2; i * i <= 100001; i++) {
    if (prime[i] == 1) {
      prime[i] = i;
      for (int j = i * i; j <= 100001; j += i) {
        if (prime[j] == 1) prime[j] = i;
      }
    }
  }
}
int gcd(long a, long b) {
  if (b == 0)
    return a;
  else
    return gcd(b, a % b);
}
int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  cout.tie(NULL);
  ;
  map<int, vector<pair<int, int>>> m;
  int n;
  cin >> n;
  vector<int> ar(n);
  vector<int> c(n);
  for (int i = 0; i < n; i++) {
    cin >> ar[i];
  }
  c[0] = ar[0];
  for (int i = 1; i < n; i++) {
    c[i] = c[i - 1] + ar[i];
  }
  int t;
  for (int i = 0; i < n; i++) {
    for (int j = i; j < n; j++) {
      t = c[j] - c[i] + ar[i];
      m[t].push_back(make_pair(j, i));
    }
  }
  vector<pair<int, int>> sol[m.size()];
  int j = 0;
  pair<int, int> prev;
  for (auto &it : m) {
    sort(it.second.begin(), it.second.end());
    prev = it.second[0];
    sol[j].push_back(prev);
    for (int i = 1; i < it.second.size(); i++) {
      if (it.second[i].second > prev.first) {
        prev = it.second[i];
        sol[j].push_back(prev);
      }
    }
    j++;
  }
  int mi = 0;
  int k = 0;
  for (int i = 0; i < m.size(); i++) {
    if (sol[i].size() > mi) {
      mi = sol[i].size();
      k = i;
    }
  }
  cout << sol[k].size();
  cout << endl;
  for (int i = 0; i < sol[k].size(); i++) {
    cout << sol[k][i].second + 1 << " " << sol[k][i].first + 1 << endl;
  }
}
