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| import java.util.*;
class Program {
public static int[] twoNumberSum(int[] array, int targetSum) {
for(int i = 0; i < array.length; i++)
{
for(int j = i + 1; j < array.length; j++)
{
if(array[i] + array[j] == targetSum)
{
return new int[]{array[i], array[j]};
}
}
}
return new int[0];
}
}
|
Time complexity O(n^2)
HashMap Time complexity O(n)
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| import java.util.*;
class Program {
public static int[] twoNumberSum(int[] array, int targetSum) {
HashMap<Integer, Integer> nums = new HashMap<>();
for(int num : array)
{
int ans = targetSum - num;
if(nums.containsKey(ans))
{
return new int[] {ans, num};
}
else
{
nums.put(num,num);
}
}
return new int[0];
}
}
|