import sys import math def main(): input = sys.stdin.read().split() ptr = 0 N = int(input[ptr]) ptr += 1 items = [] for i in range(1, N+1): c_i = int(input[ptr]) v_i = int(input[ptr+1]) ptr += 2 items.append((i, c_i, v_i)) # Sort items in descending order of value items.sort(key=lambda x: (-x[2], x[0])) # Initialize DP table INF = -math.inf dp = [[INF] * (N + 1) for _ in range(N + 1)] dp[0][0] = 0 for (i, c_i, v_i) in items: if v_i > 0: # Process positive values by taking maximum possible m for k in range(N, -1, -1): for w in range(N, -1, -1): if dp[k][w] == INF: continue max_m = min(c_i, N - k, (N - w) // i) if max_m <= 0: continue new_k = k + max_m new_w = w + max_m * i if new_k > N or new_w > N: continue new_val = dp[k][w] + max_m * v_i if new_val > dp[new_k][new_w]: dp[new_k][new_w] = new_val else: # Process non-positive values by considering all possible m for m in range(0, c_i + 1): for k in range(N, -1, -1): for w in range(N, -1, -1): if dp[k][w] == INF: continue new_k = k + m new_w = w + m * i if new_k > N or new_w > N: continue new_val = dp[k][w] + m * v_i if new_val > dp[new_k][new_w]: dp[new_k][new_w] = new_val # Compute the answer for each k for k in range(1, N+1): max_val = INF min_weight = k max_weight = N for w in range(min_weight, max_weight + 1): if dp[k][w] > max_val: max_val = dp[k][w] print(max_val) if __name__ == '__main__': main()