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 in range(N): weight = items[i][0] c_i = items[i][1] v_i = items[i][2] max_t = min(c_i, N // weight) for t in range(0, max_t+1): t_weight = t * weight t_value = t * v_i for k in range(N, -1, -1): for w in range(N, -1, -1): if dp[k][w] == INF: continue new_k = k + t new_w = w + t_weight if new_k > N or new_w > N: continue if dp[new_k][new_w] < dp[k][w] + t_value: dp[new_k][new_w] = dp[k][w] + t_value 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()