某公司每年的销售收入均比前年增加10%个百分点，按此增长比率，多少年能实现收入翻两番用FOr 循环来写

LS注意：是用for循环不是while循环
#include <stdio.h>
void main()
{
int year=0;
float a;
for(a=1;a<2;a*=1.1)year++;
pritnf("need %d years",year);
printf("\n");
return 0;
}

#include <stdio.h>
void main()
{
int year=1;float a,b;
printf("input the first year's money!!\n");
scanf("%f",&a);
b=a;
while(a<2*b)
{
a*=1.1;
year++;
}
pritnf("need %f years");
printf("\n");
}
c写的