具有两个不同边权重的图形

I'm trying to find a path between two points. Each edge in my graph has two separate weights. I already know the shortest path, if you only take the first weight into account, between the two points. What I need to do is to maximize The second weight whilst making sure the first does not exceed a constraint. The constraint is that the total of the first weight should not exceed it's total on the shortest path by more than X%. How do I go about doing that? The final solution needn't be an exact solution, as it is intended to be a heuristic.I'm trying to find a path between two points. E