Stair Case Problem (DP)

 

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?

Example :

Input : 3
Return : 3

Steps : [1 1 1], [1 2], [2 1]







int Solution::climbStairs(int n) {
int dp[n];
if(n==0) return 1;
dp[0]=1;
dp[1]=2;
for(int i=2;i<n;i++){
dp[i]=dp[i-1]+dp[i-2];
}
return dp[n-1];
}












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