Department of Mathematics Bareilly College Bareilly (M J P R University Bareilly) (INDIA)

In the present work, The authors describe two types of problem. One is the vehicle routing problem with time windows and the second problem is the pickup and delivery problem with time windows. for Optimization we use dynamic programming and branch and bound method. They will not be able to solve large-scale problems. So, we review three types of approximation algorithms. Construction methods try to build a feasible solution starting from the raw data. Iterative improvement methods start from a feasible solution and seek to improve it through a sequence of local modifications. Incomplete optimization methods use a combination of enumeration of the solution space and heuristic rules.