From : https://leetcode.com/problems/plus-one/
Given a non-negative number represented as an array of digits, plus one to the number.
The digits are stored such that the most significant digit is at the head of the list.
class Solution {
public:
vector<int> plusOne(vector<int>& digits) {
vector<int>::reverse_iterator rit = digits.rbegin();
if(rit != digits.rend()) {
int cur = *rit;
while(cur==9) {
*(rit++) = 0;
if(rit==digits.rend()) {
digits.insert(digits.begin(), 1);
return digits;
}
cur = *rit;
}
(*rit)++;
}
return digits;
}
};
public class Solution {
public int[] plusOne(int[] digits) {
if (digits == null || digits.length == 0) {
return new int[] {};
}
int carry = 1;
for (int i = digits.length - 1; i>=0 && carry!=0; --i) {
int n = digits[i] + carry;
digits[i] = n % 10;
carry = n/10;
}
if (carry != 0) {
int[] ans = new int[digits.length+1];
ans[0] = 1;
System.arraycopy(digits, 0, ans, 1, digits.length);
return ans;
}
return digits;
}
}