The authors propose a mixed strategy of tree searching that is efficient in space. The proposed method is a combination of the breadth-first strategy, the minimum-space-pebbling strategy, and the modified depth-first iterative deepening algorithms. The authors analyze the complexity of the algorithms using three parameters: the depth of the tree, the node branching factor, and the computational efficiency described as the total number of nodes generated during the search. It is concluded that the proposed method of tree searching reduces the space requirements compared to the three other above-mentioned methods, without increasing the order of the time complexity.
