LeetCode : : 66번 Plus One - C++ 풀이

https://leetcode.com/problems/plus-one/

Plus One - LeetCode

 

class Solution {
public:
    vector<int> plusOne(vector<int>& digits) {
        int len = digits.size();
        
        // 9,9 --> 9,0 --> 1, 0, 0
        // 9,9,9 --> 9,9,0 --> 9,0,0 --> 1,0,0,0
        // 4,9 --> 4,0 --> 5,0
        // 1,2,3 --> 1,2,4
        
        for(int i = len; i > 0 ; i--){
            if(digits[i-1] == 9 && i-1 == 0){
                digits[i-1] = 0;
                digits.insert(digits.begin(),1);
                return digits; 
            }
            else if(digits[i-1] == 9){
                digits[i-1] = 0;
                continue;
            }
            else{
                digits[i-1] = digits[i-1] + 1;
                return digits;
            }
        }
    return digits;
    }
};

 

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