def solve_knapsack(self, profits, weights, capacity):
    n = len(profits)
    dp = [0] * (capacity + 1)
    for i in range(n):
        for j in range(capacity, weights[i] - 1, -1):
            dp[j] = max(profits[i] + dp[j - weights[i]], dp[j])
    return dp[capacity]
    return -1