source_code: import java.io.*;
  import java.util.*;
  
  public class B{
  
  	static long []sum;
  	
  	static int n;
  
  	public static void main(String[] args) throws IOException {
  		Scanner sc=new Scanner();
  		PrintWriter out=new PrintWriter(System.out);
  		n=sc.nextInt();
  		sum=new long [n+1];
  		for(int i=1;i<=n;i++)
  			sum[i]=sc.nextInt()+sum[i-1];
  		HashMap<Long,Integer> map=new HashMap();
  		ArrayList<int []>[]adj=new ArrayList[n*n+10];
  		for(int i=0;i<adj.length;i++)
  			adj[i]=new ArrayList();
  		for(int r=1;r<=n;r++) 
  			for(int l=1;l<=n;l++) {
  				if(r<l)
  					continue;
  				long x=sum[r]-sum[l-1];
  				map.put(x, map.getOrDefault(x, map.size()));
  				adj[map.get(x)].add(new int [] {l,r});
  			}
  		int ans=0;
  		int bestIdx=0;
  		for(int idx=0;idx<adj.length;idx++)
  		{
  			ArrayList<int[]>list=adj[idx];
  			if(list.isEmpty())
  				continue;
  			int curr=1;
  			int R=list.get(0)[1];
  			for(int i=1;i<list.size();i++)
  			{
  				int []tmp=list.get(i);
  				if(tmp[0]>R)
  				{
  					R=tmp[1];
  					curr++;
  				}
  			}
  			if(curr>=ans) {
  				ans=curr;
  				bestIdx=idx;
  			}
  		}
  		out.println(ans);
  		ArrayList<int[]>list=adj[bestIdx];
  		int R=list.get(0)[1];
  		out.println(list.get(0)[0]+" "+R);
  		for(int i=1;i<list.size();i++)
  		{
  			int []tmp=list.get(i);
  			if(tmp[0]>R)
  			{
  				R=tmp[1];
  				out.println(tmp[0]+" "+tmp[1]);
  			}
  		}
  		out.close();
  
  	}
  	
  	static class Scanner
  	{
  		BufferedReader br;
  		StringTokenizer st;
  		Scanner(){
  			br=new BufferedReader(new InputStreamReader(System.in));
  		}
  		Scanner(String fileName) throws FileNotFoundException{
  			br=new BufferedReader(new FileReader(fileName));
  		}
  		String next() throws IOException {
  			while(st==null || !st.hasMoreTokens())
  				st=new StringTokenizer(br.readLine());
  			return st.nextToken();
  		}
  		String nextLine() throws IOException {
  			return br.readLine();
  		}
  		int nextInt() throws IOException{
  			return Integer.parseInt(next());
  		}
  		long nextLong()  throws NumberFormatException, IOException {
  			return Long.parseLong(next());
  		}
  		double nextDouble() throws NumberFormatException, IOException {
  			return Double.parseDouble(next());
  		}
  	}
  }
  