Submission #1188025

#	Time	Username	Problem	Language	Result	Execution time	Memory
1188025		esomer	Bouquet (EGOI24_bouquet)	Pypy 3	70 / 100	3095 ms	63588 KiB

Main

def solve():
    n = int(input())
    segments = []
    mxLR = 0
    for _ in range(n):
        l, r = map(int, input().split(" "))
        segments.append((l, r))
        mxLR = max(mxLR, max(l, r))
    
    if n <= 1000:
        dp = [0] * n
        for i in range(n):
            l, r = segments[i]
            dp[i] = 1
            for j in range(i-l-1, -1, -1):
                if j < 0: break

                l2, r2 = segments[j]
                if j + r2 < i:
                    dp[i] = max(dp[i], dp[j] + 1)
                    
        # print(dp)
        print(max(dp))
    elif mxLR <= 2:
        dp = [0] * n
        for i in range(n):
            l, r = segments[i]
            dp[i] = 1
            for j in range(max(i-10, 0), i-l):
                if j < 0: continue
                
                l2, r2 = segments[j]
                if j + r2 < i and j < i-l:
                    dp[i] = max(dp[i], dp[j] + 1)
        
        # print(dp)
        print(max(dp))
    else:
        dp = [0] * n
        for i in range(n):
            l, r = segments[i]
            dp[i] = max(dp[i-1], 1)
            for j in range(i-l-1, -1, -1):
                if j < 0: continue
                l2, r2 = segments[j]
                if j + r2 < i:
                    dp[i] = max(dp[i], dp[j] + 1)
                    break
        print(max(dp))

# let dp[i] be the maximum amount of tulips we can pick up in the i-th point, if we have boundaries l, r. then we can see that dp[i] = max(dp[i-1], dp[j] + 1)
# for some j < i such that i-j >= l and i-j >= r_j
# so now we just need to find the first tulip j in point 0, i-l such that 

solve()

Compilation message (stdout)

Compiling 'Main.py'...

=======
  adding: __main__.pyc (deflated 45%)

=======

• Subtask 1: 8 / 8
• Subtask 2: 16 / 16
• Subtask 3: 28 / 28
• Subtask 4: 18 / 18
• Subtask 5: 0 / 30