def main(): import sys input = sys.stdin.read data = input().split() idx = 0 N = int(data[idx]) idx +=1 items = [] for i in range(1, N+1): ci = int(data[idx]) vi = int(data[idx+1]) idx +=2 items.append( (i, ci, vi) ) # Initialize DP INF = -10**18 dp = [ [INF]*(N+1) for _ in range(N+1) ] dp[0][0] = 0 for i, ci, vi in items: # Split ci into binary parts parts = [] remaining = ci current = 1 while remaining > 0: if remaining >= current: parts.append(current) remaining -= current else: parts.append(remaining) remaining = 0 current *= 2 # Process each part for p in parts: for k in range(N, p-1, -1): for w in range(N, p*i -1, -1): if dp[k - p][w - p*i] != INF: new_val = dp[k - p][w - p*i] + p * vi if new_val > dp[k][w]: dp[k][w] = new_val # For each k, find the maximum value where w <= N for k in range(1, N+1): max_val = INF for w in range(N+1): if dp[k][w] > max_val: max_val = dp[k][w] print(max_val) if __name__ == "__main__": main()