Subscription Plan Selection

A company offers various subscription plans that provide different benefits. Each plan has a price, and your task is to select a combination of plans that offers maximum benefits within a specified budget without exceeding it. Input: The first line contains two integers: `M` (maximum budget) and `N` (number of plans available). The next `N` lines each contain two integers: `B_i` (benefit of the plan) and `P_i` (price of the plan). Output: Print a single integer: maximum benefit obtainable without exceeding the budget. Example: Input: 100 3 50 50 40 30 30 20 Output: 120