Controller for internal combustion engine and non-transitory computer-readable storage medium storing program for internal combustion engine

An amount of condensed water generated in an EGR passage and flowing into one cylinder in a unit period is referred to as an EGR water amount. Memory stores information indicating a corresponding relationship between a parameter related to an operation state of an internal combustion engine and a parameter related to the EGR water amount for each cylinder. When the internal combustion engine is operating, a controller acquires a value obtained by subtracting the EGR water amount of each cylinder from a reference water amount that corresponds to the operation state of the internal combustion engine as a target water injection amount of each cylinder based on the information. The controller controls each water injection valve so that the water injection valve injects the target water injection amount of each cylinder.