# In a word of riddles called Briddles, 9 numbers from 1 - 9 want to reach to the other side of the river.

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In a word of riddles called Briddles, 9 numbers from 1 - 9 want to reach to the other side of the river. Since its a world of riddles, therefore, there are some rules:

Rule-1: Maximum 3 numbers can cross at a time.
Rule-2: River cannot sail on its own.
Rule-3: The sum of numbers crossing at a time must be a square number.

You need to plan trips such that minimum trips are needed for all numbers to cross.

posted Nov 21, 2019

7 Trips

Send 2+5+9 = 16
Bring back 9
Send 3+4+9 = 16
Bring back 9
Send 1+7+8 = 16
Bring back 1
Send 1+6+9 = 16

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