online_judge_1205

#include <stdio.h>#include <stdlib.h>int main(){    int n,i;    long long result,a,b;    while(~scanf("%d",&n))    {        if(n<1||n>90)continue;        result=0;        a=0;        b=1;        for(i=0;i<n;i++)        {            result=a+b;            a=b;            b=result;        }        printf("%lld\n",result);    }    return 0;}