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# IQuoter

Quoter Interface

Supports quoting the calculated amounts from exact input or exact output swaps

*Developer note: These functions are not marked view because they rely on calling non-view functions and reverting to compute the result. They are also not gas efficient and should not be called on-chain. Credit to Uniswap Labs under GPL-2.0-or-later license: <https://github.com/Uniswap/v3-periphery>*

## Functions

### quoteExactInput

`function quoteExactInput(bytes path, uint256 amountIn) external returns (uint256 amountOut, uint16[] fees)` external

Returns the amount out received for a given exact input swap without executing the swap

| Name     | Type    | Description                                |
| -------- | ------- | ------------------------------------------ |
| path     | bytes   | The path of the swap, i.e. each token pair |
| amountIn | uint256 | The amount of the first token to swap      |

**Returns:**

| Name      | Type      | Description                                         |
| --------- | --------- | --------------------------------------------------- |
| amountOut | uint256   | The amount of the last token that would be received |
| fees      | uint16\[] |                                                     |

### quoteExactInputSingle

`function quoteExactInputSingle(address tokenIn, address tokenOut, uint256 amountIn, uint160 limitSqrtPrice) external returns (uint256 amountOut, uint16 fee)` external

Returns the amount out received for a given exact input but for a swap of a single pool

| Name           | Type    | Description                                                     |
| -------------- | ------- | --------------------------------------------------------------- |
| tokenIn        | address | The token being swapped in                                      |
| tokenOut       | address | The token being swapped out                                     |
| amountIn       | uint256 | The desired input amount                                        |
| limitSqrtPrice | uint160 | The price limit of the pool that cannot be exceeded by the swap |

**Returns:**

| Name      | Type    | Description                                       |
| --------- | ------- | ------------------------------------------------- |
| amountOut | uint256 | The amount of \`tokenOut\` that would be received |
| fee       | uint16  |                                                   |

### quoteExactOutput

`function quoteExactOutput(bytes path, uint256 amountOut) external returns (uint256 amountIn, uint16[] fees)` external

Returns the amount in required for a given exact output swap without executing the swap

| Name      | Type    | Description                                                                        |
| --------- | ------- | ---------------------------------------------------------------------------------- |
| path      | bytes   | The path of the swap, i.e. each token pair. Path must be provided in reverse order |
| amountOut | uint256 | The amount of the last token to receive                                            |

**Returns:**

| Name     | Type      | Description                                   |
| -------- | --------- | --------------------------------------------- |
| amountIn | uint256   | The amount of first token required to be paid |
| fees     | uint16\[] |                                               |

### quoteExactOutputSingle

`function quoteExactOutputSingle(address tokenIn, address tokenOut, uint256 amountOut, uint160 limitSqrtPrice) external returns (uint256 amountIn, uint16 fee)` external

Returns the amount in required to receive the given exact output amount but for a swap of a single pool

| Name           | Type    | Description                                                     |
| -------------- | ------- | --------------------------------------------------------------- |
| tokenIn        | address | The token being swapped in                                      |
| tokenOut       | address | The token being swapped out                                     |
| amountOut      | uint256 | The desired output amount                                       |
| limitSqrtPrice | uint160 | The price limit of the pool that cannot be exceeded by the swap |

**Returns:**

| Name     | Type    | Description                                                                     |
| -------- | ------- | ------------------------------------------------------------------------------- |
| amountIn | uint256 | The amount required as the input for the swap in order to receive \`amountOut\` |
| fee      | uint16  |                                                                                 |