aSIo5l - Online Java Compiler & Debugging Tool

/* package whatever; // don't place package name! */

import java.util.*;
import java.lang.*;
import java.io.*;

/* Name of the class has to be "Main" only if the class is public. */
class Ideone
{
	public static void main (String[] args) throws java.lang.Exception
	{
		// your code goes here
		Scanner sc=new Scanner(System.in);
		int n=sc.nextInt();
		int m=sc.nextInt();
		int arr[][]=new int[n][2];
		for(int i=0;i<n;i++){
			arr[i][0]=sc.nextInt();
			arr[i][1]=sc.nextInt();
		}
		int dp[][]=new int[n+1][2];
		dp[1][0]=arr[0][0];
		dp[1][1]=arr[0][1];
		for(int i=2;i<=n;i++){
			dp[i][0]=dp[i-1][0]+arr[i-1][0];
			dp[i][1]=Math.max(dp[i-2][0],dp[i-2][1])+arr[i-1][1];
		}
		System.out.println(Math.max(dp[n][0],dp[n][1]));
	}
}