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)) # Initialize DP table INF = -float('inf') dp = [[INF] * (N + 1) for _ in range(N + 1)] dp[0][0] = 0 for (i, c_i, v_i) in items: # Process item type i, taking t items (1 <= t <= c_i) max_t = min(c_i, N) for t in range(1, max_t + 1): weight = i * t value = v_i * t # Update DP in reverse order to avoid overwriting for k in range(N, t - 1, -1): for s in range(N, weight - 1, -1): if dp[k - t][s - weight] != INF: if dp[k][s] < dp[k - t][s - weight] + value: dp[k][s] = dp[k - t][s - weight] + value # Compute the answer for each k for k in range(1, N + 1): max_val = INF for s in range(k, N + 1): if dp[k][s] > max_val: max_val = dp[k][s] print(max_val) if __name__ == "__main__": main()