def main(): import sys input = sys.stdin.read data = input().split() N = int(data[0]) items = [] index = 1 for i in range(N): c_i = int(data[index]) v_i = int(data[index + 1]) items.append((c_i, v_i)) index += 2 INF = -10**18 dp = [[INF] * (N + 1) for _ in range(N + 1)] dp[0][0] = 0 for idx in range(N): i = idx + 1 # item type (weight) c_i, v_i = items[idx] remaining = c_i t = 1 while remaining > 0: take = min(t, remaining) # Update DP in reverse order for k in range(N, -1, -1): for w in range(N, -1, -1): if dp[k][w] == INF: continue new_k = k + take new_w = w + take * i if new_k > N or new_w > N: continue if dp[new_k][new_w] < dp[k][w] + take * v_i: dp[new_k][new_w] = dp[k][w] + take * v_i remaining -= take t *= 2 # Compute answers for k in range(1, N + 1): max_val = max(dp[k][k:N+1]) print(max_val) if __name__ == "__main__": main()