def main():
    import sys
    input = sys.stdin.read().split()
    idx = 0
    N = int(input[idx])
    idx += 1
    K = int(input[idx])
    idx += 1
    pizzas = []
    for _ in range(N):
        p = int(input[idx])
        idx += 1
        d = int(input[idx])
        idx += 1
        pizzas.append((p, d))
    
    # 按价格从高到低排序
    pizzas.sort(reverse=True, key=lambda x: x[0])
    
    # 初始化dp数组
    INF = float('-inf')
    dp = [ [INF] * 2 for _ in range(K+1) ]
    dp[0][0] = 0  # 初始状态：支付0元，无免费机会，美味度为0
    
    for p, d in pizzas:
        # 创建临时dp数组，用于保存当前的状态
        temp_dp = [row[:] for row in dp]
        for c in range(K+1):
            for b in [0, 1]:
                if temp_dp[c][b] == INF:
                    continue
                # 选项二：购买当前披萨
                if b == 0:
                    new_c = c + p
                    if new_c <= K:
                        new_b = 1
                        new_d = temp_dp[c][b] + d
                        if new_d > dp[new_c][new_b]:
                            dp[new_c][new_b] = new_d
                # 选项三：免费拿当前披萨
                if b == 1:
                    new_c = c
                    new_b = 0
                    new_d = temp_dp[c][b] + d
                    if new_d > dp[new_c][new_b]:
                        dp[new_c][new_b] = new_d
    
    # 找出最大值
    max_d = 0
    for c in range(K+1):
        for b in [0, 1]:
            if dp[c][b] > max_d:
                max_d = dp[c][b]
    print(max_d)

if __name__ == "__main__":
    main()