PTA 7-5 兔子繁衍问题 (15分)

Posted 2021-03-04

#include<stdio.h>
int main()
{
    int x,i;
    int a=2, b=0, c=0;
    scanf("%d", &x);
    if (x > 1)
    {
        for (i = 1; c < x; i++)
        {
            c = a + b;
            b = a;
            a = c;
        }
        printf("%d", i+1);
    }
    else
        printf("1");
    return 0;
}