Editorial for COCI '06 Contest 2 #3 Kolone

Remember to use this editorial only when stuck, and not to copy-paste code from it. Please be respectful to the problem author and editorialist.
Submitting an official solution before solving the problem yourself is a bannable offence.

One approach is to simulate the ants' behaviour second by second.

A more efficient approach directly calculates the final position of each ant.

Let's label the ants with numbers within their rows, starting with $0$ $0$ .

We know the initial ( $T = 0$ $T = 0$ ) position $P$ $P$ of each ant: $P = N_1-i-i_1$ $P = N_{1} - i - i_{1}$ for the first (left) row and $P = N_1+I$ $P = N_{1} + I$ for the other (right).

There are three cases:

If $T$ $T$ is less than $i$ $i$ , then the ant will not jump over any other ants and will remain in its initial position.
If $T$ $T$ is greater than or equal to $i+$ $i +$ (the number of ants in the other row), then the ant will jump over all of the ants in the other row.
Otherwise, the ant's position will change by $T-i$ $T - i$ .

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