Given two non-negative integers num1 and num2 rePResented as string, return the sum of num1 and num2. Note: The length of both num1 and num2 is < 5100. Both num1 and num2 contains only digits 0-9. Both num1 and num2 does not contain any leading zero. You must not use any built-in BigInteger library or convert the inputs to integer directly.
class Solution {public: string addStrings(string num1, string num2) { int i = num1.length() - 1; int j = num2.length() - 1; string str; int carry = 0; while( i >= 0 || j >= 0 || carry){ int sum = 0; if( i >= 0) sum += num1[i--] - '0'; if( j >= 0) sum += num2[j--] - '0'; sum += carry; carry = sum / 10; sum %= 10; str += to_string(sum); } reverse(str.begin(), str.end()); return str; }};新闻热点
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