Transaction

[Error Code: 1101] error caused by: 1 error occurred:
	* transaction invocation failed when executing transaction: [Error Code: 1101] cadence runtime error: Execution failed:
error: underflow
  --> c72cefc4920bc21b10be3f9e25fbe7e850d8794f3ffcc2f6e31fb036d820701d:18:8
   |
18 |         let f1 = fee * I1B2sqr / scale * I2B1sqr / scale - I1B2;
   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^