为什么编写c程序时，200*5*0.85等于849？？？？

Question

不应该等于850吗？？？
#include
int main(void)
{
const int danjia = 5;
int shuliang = 0;
int zongjia = 0;
int zan = 0;
printf("shurushuliang:");
scanf("%d",&shuliang);
zan = shuliang * danjia;
if((zan > 30) && (zan <= 50))
zongjia = shuliang*danjia*0.9;
printf("%d",zongjia);
if(zan > 50)
{
zongjia = shuliang*danjia*0.85;
printf("%d",zongjia);
}
else
printf("%d",shuliang*danjia);
return 0;
}

Answer 1

这完全是因为浮点型计算精度的问题
0.85 在实际参与运算进，可能是 0.8499999999999，而导致结果是 849.