You are climbing a stair case. It takes n steps to reach to the top.
Each time you can either climb 1 or 2 steps. In how many distinct ways can you climb to the top?
容易
int climbStairs(int n) {
if (n <= 2) {
return n;
} else {
int *step = new int[n+1];
step[1] = 1;
step[2] = 2;
for (int i = 3; i <= n; ++i) {
step[i] = step[i-1] + step[i-2];
}
int tmp = step[n];
delete step;
return tmp;
}
}