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
  --> 612ae9d1f7ae0385f5aca53dbeb68adcf28de07452acb49e52a1d239b6e319e5:18:8
   |
18 |         let f1 = fee * I1B2sqr / scale * I2B1sqr / scale - I1B2;
   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^