#include <stdio.h>
int feibo(int n)
{
int a,b,c;
a=1;
b=1;
c=1;
while(n>2)
{
c=a+b;
a=b;
b=c;
n--;
}
return c;
}
int main()
{
int n;
scanf("%d",&n);
int ret=feibo(n);
printf("ret=%d",ret);
return 0;
}
#include <stdio.h>
int feibo(int n)
{
int a,b,c;
a=1;
b=1;
c=1;
while(n>2)
{
c=a+b;
a=b;
b=c;
n--;
}
return c;
}
int main()
{
int n;
scanf("%d",&n);
int ret=feibo(n);
printf("ret=%d",ret);
return 0;
}