scanf

iIntegerAny number of digits, optionally preceded by a sign (+ or -).
Decimal digits assumed by default (0-9), but a 0 prefix introduces octal digits (0-7), and 0x hexadecimal digits (0-f).
Signed argument.
d or uDecimal integerAny number of decimal digits (0-9), optionally preceded by a sign (+ or -).
d is for a signed argument, and u for an unsigned.
oOctal integerAny number of octal digits (0-7), optionally preceded by a sign (+ or -).
Unsigned argument
xHexadecimal integerAny number of hexadecimal digits (0-9, a-f, A-F), optionally preceded by 0x or 0X, and all optionally preceded by a sign (+ or -).
Unsigned argument
f, e, g, aFloating point number
cCharacter
sString of characters