const REGEX_POSTIVE = /(?<=\-)\d+/

const c = '03-6382020'.match(REGEX_POSTIVE); //6382020

const d = '054-5555555'.match(REGEX_POSTIVE); //5555555

const REGEX_NEGATIVE = /(?<!\$)\d/

const e = '$4'.match(REGEX_NEGATIVE); //false

const f = '₪4'.match(REGEX_NEGATIVE); // 4

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