如何在“ C”中保留小数点后抑制或消除零

Question

My program is below, this is for class. My question is what should I be adding to my program to either stop or eliminate the '.' decimals and zeros trailing after my answer is printed.

// Ch5Pgm7.cpp : Takes a number entered by the user and cubes it.
//Written by: Chris Howard       Sept. 25th 2014.

#include "stdafx.h"
#include "stdio.h"

void cube(double NUM);      // My function that will cube the users input

int main(void)
{
double NUM;
printf("Please enter a number: ");
scanf_s("%lf", &NUM);
cube(NUM);

return 0;
}

void cube(double NUM)
{
NUM = NUM * NUM * NUM;

printf("%lf\n", NUM);
}

Answer 1

Use . and the number of decimal spaces you want.

printf("%.0lf\n", NUM);

Answer 2

假设您要坚持浮点运算，并且不想使用整数，则可以使用g转换说明符：

printf("%g\n", NUM);

Answer 3

you can use the g specifier to get rid of the decimal . and the trailing zeroes

printf("%.0g", NUM);