detect error if number of 1 or 0 bits seems wrong as the parity bit (row in 2d matrix). then add error correction codes (other parity bits representing column in 2d matrix). if both parity bit and error correction code seem wrong, you can figure out the exact bit (coordinate) that seems wrong.
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パリティビットの意味と誤り検出、誤り訂正の方法 - 具体例で学ぶ数学
Error correction | Journey into information theory | Computer Science | Khan Academy
