я не сомневаюсь что к концу недели

я не сомневаюсь что к концу недели будет найдено оптимальное решение этой непростой проблемы

Results (English) 1:

I have no doubt that by the end of the week will find the optimal solution of this difficult problem

Results (English) 2:

I have no doubt that by the end of the week will be found an optimal solution to this complex problem

Results (English) 3:

I have no doubt that by the end of the week will be found the optimal solution to this complex problem