在阵列中找到具有给定差异的2个项的算法

def find_diff_pairs(arr, target_diff):
    hash_set = set()
    for num in arr:
        if num - target_diff in hash_set:
            return (num - target_diff, num)
        hash_set.add(num)
    return None

arr = [1, 5, 3, 8, 9, 12]
target_diff = 4
result = find_diff_pairs(arr, target_diff)
if result:
    print(f"找到差异为 {target_diff} 的2个项：{result[0]} 和 {result[1]}")
else:
    print(f"在阵列中未找到差异为 {target_diff} 的2个项")