Unresolved compilation problem in Java

In this Program i am going to display sum of 1 to n numbers in Java.

Error Message:

Exception in thread "main" java.lang.Error: Unresolved compilation problem:

       Duplicate local variable i

       at com.lib.SumOf1ton.main(SumOf1ton.java:13)

Error Description:

In below program input is stored in variable i and in for loop index variable is also i,so i got an error.

package com.lib;

import java.util.Scanner;

public class SumOf1ton

{

       public static void main(String[] args)

       {

              int Sum = 0,m;

              Scanner rv = new Scanner(System.in);

              System.out.println("enter value of m:");

              int i = rv.nextInt();

              for(int i=1;i<=m;i++)

              {

                     Sum += i;

              }

              System.out.println(Sum);

       }

}

Error Solution:

package com.lib;

import java.util.Scanner;

public class SumOf1ton

{

       public static void main(String[] args)

       {

              int Sum = 0;

              Scanner rv = new Scanner(System.in);

              System.out.println("enter value of m:");

              int m = rv.nextInt();

              for(int i=1;i<=m;i++)

              {

                     Sum += i;

              }

              System.out.println(Sum);

       }

}

Output:

enter value of m:

4

10