#include <stdio.h>
int stair(int n){
if(n==1) return 1;
if(n==2) return 2;
int totalways= stair(n-1)+stair(n-2);
return totalways;
}
int main() {
int n;
printf("Enter the value of n: \n"); int ways= stair(n);
return 0;
}
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