Solution: Add Strings

Statement▼

Given two non-negative integers, num1 and num2, represented as strings, return the sum of num1 and num2 as a string.

You must not use any built-in library for handling large integers (such as BigInteger) or directly convert the inputs to integers.

Constraints:

$1 \leq$ num1.length, num2.length $\leq 10^3$
num1 and num2 consist of only digits.
num1 and num2 don’t have any leading zeros except for the zero itself.

The problem requires adding two non-negative integers represented as strings without directly converting them into numeric types or using built-in big integer operations. This means that if num1 = “ $284$ ” and num2 = “ $150$ ”, then while we can’t directly convert “ $284$ ” to $284$ , or “ $150$ ” to $150$ , we can consider their individual digits as numerics, i.e., “ ...

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Grokking the Coding Interview Patterns

Solution: Add Strings

Statement▼

Given two non-negative integers, num1 and num2, represented as strings, return the sum of num1 and num2 as a string.

You must not use any built-in library for handling large integers (such as BigInteger) or directly convert the inputs to integers.

Constraints:

$1 \leq$ num1.length, num2.length $\leq 10^3$
num1 and num2 consist of only digits.
num1 and num2 don’t have any leading zeros except for the zero itself.