**How to reproduce**
```
SELECT
    intervalLengthSum(10, 5) AS res,
    toInt64(res) AS cast,
    toTypeName(res) AS type

Query id: bc8307c2-a520-4499-959e-bb00e0bdf055

┌──────────────────res─┬─cast─┬─type───┐
│ 18446744073709551611 │   -5 │ UInt64 │
└──────────────────────┴──────┴────────┘
```
**Expected behavior**
intervals with negative sum will be converted to zero.
#pragma once
#include <AggregateFunctions/AggregateFunctionNull.h>
#include <Columns/ColumnsNumber.h>
#include <Common/ArenaAllocator.h>
#include <Common/assert_cast.h>
#include <DataTypes/DataTypeDateTime.h>
#include <DataTypes/DataTypesNumber.h>
#include <IO/ReadHelpers.h>
#include <IO/WriteHelpers.h>