What is the its normal solution


#1

Comment body goes here.


#2

int Solution::climbStairs(int A) {
int n = A;
if(n == 1) return 1;
int stepPrePre = 1;
int stepPre = 1;
int current;
for(int i = 2; i <= n; i++) {
current = stepPrePre + stepPre;
stepPrePre = stepPre;
stepPre = current;
}
return current;
}