# SafeMath

## Overview

#### License: MIT

```solidity
library SafeMath
```

Wrappers over Solidity's arithmetic operations.

NOTE: `SafeMath` is generally not needed starting with Solidity 0.8, since the compiler now has built in overflow checking.

## Functions info

### tryAdd

```solidity
function tryAdd(uint256 a, uint256 b) internal pure returns (bool, uint256)
```

Returns the addition of two unsigned integers, with an overflow flag.

*Available since v3.4.*

### trySub

```solidity
function trySub(uint256 a, uint256 b) internal pure returns (bool, uint256)
```

Returns the substraction of two unsigned integers, with an overflow flag.

*Available since v3.4.*

### tryMul

```solidity
function tryMul(uint256 a, uint256 b) internal pure returns (bool, uint256)
```

Returns the multiplication of two unsigned integers, with an overflow flag.

*Available since v3.4.*

### tryDiv

```solidity
function tryDiv(uint256 a, uint256 b) internal pure returns (bool, uint256)
```

Returns the division of two unsigned integers, with a division by zero flag.

*Available since v3.4.*

### tryMod

```solidity
function tryMod(uint256 a, uint256 b) internal pure returns (bool, uint256)
```

Returns the remainder of dividing two unsigned integers, with a division by zero flag.

*Available since v3.4.*

### add

```solidity
function add(uint256 a, uint256 b) internal pure returns (uint256)
```

Returns the addition of two unsigned integers, reverting on overflow.

Counterpart to Solidity's `+` operator.

Requirements:

* Addition cannot overflow.

### sub

```solidity
function sub(uint256 a, uint256 b) internal pure returns (uint256)
```

Returns the subtraction of two unsigned integers, reverting on overflow (when the result is negative).

Counterpart to Solidity's `-` operator.

Requirements:

* Subtraction cannot overflow.

### mul

```solidity
function mul(uint256 a, uint256 b) internal pure returns (uint256)
```

Returns the multiplication of two unsigned integers, reverting on overflow.

Counterpart to Solidity's `*` operator.

Requirements:

* Multiplication cannot overflow.

### div

```solidity
function div(uint256 a, uint256 b) internal pure returns (uint256)
```

Returns the integer division of two unsigned integers, reverting on division by zero. The result is rounded towards zero.

Counterpart to Solidity's `/` operator.

Requirements:

* The divisor cannot be zero.

### mod

```solidity
function mod(uint256 a, uint256 b) internal pure returns (uint256)
```

Returns the remainder of dividing two unsigned integers. (unsigned integer modulo), reverting when dividing by zero.

Counterpart to Solidity's `%` operator. This function uses a `revert` opcode (which leaves remaining gas untouched) while Solidity uses an invalid opcode to revert (consuming all remaining gas).

Requirements:

* The divisor cannot be zero.

### sub

```solidity
function sub(
    uint256 a,
    uint256 b,
    string memory errorMessage
) internal pure returns (uint256)
```

Returns the subtraction of two unsigned integers, reverting with custom message on overflow (when the result is negative).

CAUTION: This function is deprecated because it requires allocating memory for the error message unnecessarily. For custom revert reasons use {trySub}.

Counterpart to Solidity's `-` operator.

Requirements:

* Subtraction cannot overflow.

### div

```solidity
function div(
    uint256 a,
    uint256 b,
    string memory errorMessage
) internal pure returns (uint256)
```

Returns the integer division of two unsigned integers, reverting with custom message on division by zero. The result is rounded towards zero.

Counterpart to Solidity's `/` operator. Note: this function uses a `revert` opcode (which leaves remaining gas untouched) while Solidity uses an invalid opcode to revert (consuming all remaining gas).

Requirements:

* The divisor cannot be zero.

### mod

```solidity
function mod(
    uint256 a,
    uint256 b,
    string memory errorMessage
) internal pure returns (uint256)
```

Returns the remainder of dividing two unsigned integers. (unsigned integer modulo), reverting with custom message when dividing by zero.

CAUTION: This function is deprecated because it requires allocating memory for the error message unnecessarily. For custom revert reasons use {tryMod}.

Counterpart to Solidity's `%` operator. This function uses a `revert` opcode (which leaves remaining gas untouched) while Solidity uses an invalid opcode to revert (consuming all remaining gas).

Requirements:

* The divisor cannot be zero.