In the lecture, you worked on the toDollars function which formats a number in the form $ $1,234\mathrm{.}25.$ Write a more generalized format$()$ function that works like this:

double amt $=1234\mathrm{.}25$;

cout $<<$ format$($amount$)$; $//$ default formatting

cout $<<$ format$($amount$,\mathrm{.}2)$; $//$ fixed, $2$ decimals

cout $<<$ format$($amount$,12\mathrm{.}2)$; $//$ width $12,$ fixed, $2$ decimals

cout $<<$ format$($amount$,12\mathrm{.}2,"")$; $//$ width $12,$ fixed, $2$ decimals, Euro