How do I set the precision of a floating variable in C++?

Question

我已经尝试过setprecision()方法，但 IDE 显示“未在范围内声明”错误。

Answer 1

In order to allow for std::precision() you should look at the example below:

#include <iomanip>
#include <iostream>

int main() { 
    std::cout << std::setprecision(5) << 3.44444444444 << std::endl;
}