Reading the Clue Sum

Level: Basic

First work out the minimum length that a line's number clues require.

The starting point for solving nonograms is knowing the minimum length that a line's clues take up. Add all the clue numbers together, then add the minimum gaps required between blocks (number of blocks − 1), and you get how many cells that line must use at the very least.

For example, in a line of length 10 with the clue "4 3", you need at least 4+3+1 = 8 cells. The closer this value is to the length of the line, the more the block positions are constrained and the more confirmed cells appear.

By first estimating each line's minimum length at a glance, you can judge which lines to tackle first to produce confirmed cells fastest.

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