We want to change money for our summer travel. At the exchange office $n$ currencies are handled. For one unit of the $j$ th type we have to pay $r_{ij}$ units of the $i$ th type. $($E$.$g$.$ if the $j$ th is the US dollar, and the $i$ th is the forint, then $r_{ij}=348$ approximately.$).$ Using the array $r_{ij}$; give an algorithm which determines the best exchange rate from our currency to the one used at our destination in $c*n^3$ steps, if we suppose that there is no commission at the office. $($We can change currency $i$ to currency $j$ in more than one steps.$)$