C语言 将华氏度转换为摄氏度的 C 程序总是打印零
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C program to convert Fahrenheit to Celsius always prints zero
提问by James
I need some help with a program for converting Fahrenheit to Celsius in C. My code looks like this
我需要在 C 中将华氏温度转换为摄氏温度的程序方面的帮助。我的代码如下所示
#include <stdio.h>
int main(void)
{
int fahrenheit;
double celsius;
printf("Enter the temperature in degrees fahrenheit:\n\n\n\n");
scanf("%d", &fahrenheit);
celsius = (5 / 9) * (fahrenheit - 32);
printf("The converted temperature is %lf\n", celsius);
return 0;
}
Every time I execute it it the result is 0.000000. I know I'm missing something but can't figure out what.
每次我执行它时，结果都是 0.000000。我知道我错过了一些东西，但无法弄清楚是什么。
回答by nybbler
5/9 will result in integer division, which will = 0
5/9 将导致整数除法，这将 = 0
Try 5.0/9.0instead.
试试吧5.0/9.0。
回答by Incognito
You problem is here :
你的问题在这里：
celsius = (5/9) * (fahrenheit-32);
5/9will always give you 0. Use (5.0/9.0) instead.
5/9永远给你0。请改用 ( 5.0/9.0)。
回答by Vladimir Ivanov
try celsius = ((double)5/9) * (fahrenheit-32);Or you can use 5.0.
尝试celsius = ((double)5/9) * (fahrenheit-32);或者您可以使用 5.0。
The fact is that "/" looks at the operand type. In case of int the result is also an int, so you have 0. When 5 is treated as double, then the division will be executed correctly.
事实是“/”查看操作数类型。在 int 的情况下，结果也是一个 int，所以你有 0。当 5 被视为 double 时，那么除法将正确执行。
回答by Jonathan Wood
You need to use floating point arithmetic in order to perform these type of formulas with any accuracy. You can always convert the final result back to an integer, if needed.
您需要使用浮点运算才能以任何精度执行这些类型的公式。如果需要，您始终可以将最终结果转换回整数。
回答by Foo Bah
write 5/9.0instead of 5/9 -- this forces double division
写5/9.0而不是 5/9 - 这会强制双除
回答by TheBuzzSaw
When dealing with floats, it needs to be 5.0f / 9.0f.
处理浮点数时，需要5.0f/9.0f。
When dealing with doubles, it needs to be 5.0 / 9.0.
处理双打时，需要5.0/9.0。
When dealing with integers, remainders/fractions are always truncated. 5 / 9 results between 0 and 1, so it is truncated to just 0 every time. That multiplies the other side by zero and completely nullifies your answer every time.
处理整数时，余数/分数总是被截断。5 / 9 结果介于 0 和 1 之间，因此每次都会被截断为 0。这会将另一边乘以零，并且每次都完全使您的答案无效。
回答by Pankaj Prakash
5and 9are of inttype
hence 5/9will always result 0.
5并且9是int类型，
因此5/9总是会导致0。
You can use 5/9.0or 5.0/9or 5.0/9.0
您可以使用5/9.0或5.0/9或5.0/9.0
You can also check C program for converting Fahrenheit into Celsius
您还可以查看C 程序将华氏温度转换为摄氏温度
回答by paul
using System;
public class Calculate
{
public static void Main(string[] args)
{
//define variables
int Celsius;
int fahrenheit;
string input;
//prompt for input
//read in the input and convert
Console.WriteLine("Enter Celsius temperature");
input = Console.ReadLine();
Celsius = Convert.ToInt32(input);
//calculate the result
fahrenheit = ((Celsius * 9 )/5) + 32;
//print to screen the result
Console.WriteLine("32 degrees Celsius is {0}", "equivilant to 89.60 degrees fahrenheit");
Console.ReadLine();
}
