def main(): import sys input = sys.stdin.read().split() idx = 0 N = int(input[idx]) idx += 1 items = [] for i in range(1, N+1): c_i = int(input[idx]) v_i = int(input[idx+1]) idx +=2 items.append( (i, c_i, v_i) ) INF = -10**18 dp = [ [INF]*(N+1) for _ in range(N+1) ] dp[0][0] = 0 for (i, c_i, v_i) in items: for m in range(1, c_i+1): if m * i > N: break for k in range(N, m-1, -1): for w in range(N, m*i-1, -1): if dp[k - m][w - m*i] != INF: if dp[k][w] < dp[k - m][w - m*i] + m * v_i: dp[k][w] = dp[k - m][w - m*i] + m * v_i for k in range(1, N+1): max_val = INF for w in range(k, N+1): if dp[k][w] > max_val: max_val = dp[k][w] print(max_val) if __name__ == '__main__': main()