C++: Formatted Numeric Output

Bjarne-stroustrup
 

Express a number in decimal as a fixed-length string with leading zeros.

For example, the number 7.125 could be expressed as “00007.125”.

#include <iostream>
#include <iomanip>

int main()
{
	std::cout << std::setfill('0') << std::setw(9) << std::fixed << std::setprecision(3) << 7.125 << std::endl;
	return 0;
}

SOURCE

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