JSFiddle - React, Tailwind, and code Playground

by rga4

JavaScript

emso = '5011981500121'; // ИСХОДНЫЕ ДАННЫЕ

emso_sum = 0;
for (i = 7; i > 1; i--) {
  emso_sum += i * (Number(emso[7 - i]) + Number(emso[13 - i]));
};
  if (emso_sum % 11 == 0) {
  	control_digit = 0;
  } else {
  	control_digit = 11 - (emso_sum % 11);
  }  


console.log(control_digit, "0") // РЕЗУЛЬТАТ