double 和 float 的有效数字位数？？？
#include <stdio.h>int main(void)
{
int all_water_quality=950;
double one_water_molecules=3.0e-23;
double all_water_molecules_number;
all_water_molecules_number=all_water_quality/one_water_molecules;
printf("all_water_molecules_number:%lf\n or %le",all_water_molecules_number,
all_water_molecules_number);
getch();
}
结果：
为何两种结果的有效数字不一样？？？
