source_code: import java.io.*;
  import java.util.ArrayList;
  import java.util.Collections;
  import java.util.HashMap;
  import java.util.StringTokenizer;
  
  public class Solution {
      static final int INF = (int) 1e9;
      static final int mod = (int) (1e9 + 7);
      static final short UNCALC = -1;
  
  
      public static void main(String[] args) throws IOException {
          Scanner sc = new Scanner(System.in);
          PrintWriter out = new PrintWriter(System.out);
          int n = sc.nextInt();
          int[] a = sc.nextIntArray(n);
          long[] cum = new long[n];
          cum[0] = a[0];
          for (int i = 1; i < n; i++)
              cum[i] = a[i] + cum[i - 1];
          HashMap<Long, ArrayList<Pair>> hm = new HashMap<>();
          for (int i = 0; i < n; i++) {
              for (int j = i; j < n; j++) {
                  long cur = get(cum, i, j);
                  if (!hm.containsKey(cur)) hm.put(cur, new ArrayList<>());
                  hm.get(cur).add(new Pair(i, j));
              }
          }
          int max = 0;
          StringBuilder ans = new StringBuilder();
          for (long sum : hm.keySet()) {
              ArrayList<Pair> cur = hm.get(sum);
              Collections.sort(cur);
              int poss = 0;
              int r = -1;
              StringBuilder sb = new StringBuilder();
              for (int i = 0; i < cur.size(); i++) {
                  if (cur.get(i).left > r) {
                      poss++;
                      r = cur.get(i).right;
                      sb.append(cur.get(i));
                  }
              }
              if (poss> max){
                  max = poss;
                  ans = sb;
              }
          }
          out.println(max);
          out.println(ans);
          out.flush();
          out.close();
      }
  
      static long get(long[] a, int i, int j) {
          return a[j] - (i > 0 ? a[i - 1] : 0);
      }
  
      static class Pair implements Comparable<Pair> {
          int left, right;
  
          public Pair(int left, int right) {
              this.left = left;
              this.right = right;
          }
  
          @Override
          public int compareTo(Pair o) {
              return right - o.right;
          }
  
          @Override
          public String toString() {
              return (left + 1) + " " + (right + 1) + "\n";
          }
      }
  
      static class Scanner {
          StringTokenizer st;
          BufferedReader br;
  
          public Scanner(InputStream system) {
              br = new BufferedReader(new InputStreamReader(system));
          }
  
          public Scanner(String file) throws Exception {
              br = new BufferedReader(new FileReader(file));
          }
  
          public String next() throws IOException {
              while (st == null || !st.hasMoreTokens()) st = new StringTokenizer(br.readLine());
              return st.nextToken();
          }
  
          public String nextLine() throws IOException {
              return br.readLine();
          }
  
          public int nextInt() throws IOException {
              return Integer.parseInt(next());
          }
  
          public double nextDouble() throws IOException {
              return Double.parseDouble(next());
          }
  
          public char nextChar() throws IOException {
              return next().charAt(0);
          }
  
          public Long nextLong() throws IOException {
              return Long.parseLong(next());
          }
  
          public boolean ready() throws IOException {
              return br.ready();
          }
  
          public void waitForInput() throws InterruptedException {
              Thread.sleep(3000);
          }
  
          public int[] nextIntArray(int n) throws IOException {
              int[] a = new int[n];
              for (int i = 0; i < n; i++)
                  a[i] = nextInt();
              return a;
          }
  
          public Integer[] nextIntegerArray(int n) throws IOException {
              Integer[] a = new Integer[n];
              for (int i = 0; i < n; i++)
                  a[i] = nextInt();
              return a;
          }
  
          public double[] nextDoubleArray(int n) throws IOException {
              double[] ans = new double[n];
              for (int i = 0; i < n; i++)
                  ans[i] = nextDouble();
              return ans;
          }
  
          public short nextShort() throws IOException {
              return Short.parseShort(next());
          }
  
      }
  }