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 = -float('inf') dp = [[INF] * (N + 1) for _ in range(N + 1)] dp[0][0] = 0 for (i, c_i, v_i) in items: for k in range(N, -1, -1): for w in range(N, -1, -1): if dp[k][w] == INF: continue max_t = min(c_i, (N - k) // 1, (N - w) // i) if max_t <= 0: continue for t in range(1, max_t + 1): new_k = k + t new_w = w + t * i if new_k > N or new_w > N: continue if dp[new_k][new_w] < dp[k][w] + t * v_i: dp[new_k][new_w] = dp[k][w] + t * 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()