<pre class="cpp" name="code">class Solution {
public:
int addDigits(int num) {
return num-(num-1)/9*9;
//return num?1+(num-1)%9:0;
//return 1+(num-1)%9; //-1%9=-1
}
};
<pre class="cpp" name="code">class Solution {
public:
int addDigits(int num) {
return num-(num-1)/9*9;
//return num?1+(num-1)%9:0;
//return 1+(num-1)%9; //-1%9=-1
}
};