ИМКТ 2021 маг. Python - Formatting function

Problem F. Formatting function ≡

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Author:	A. Klenin	Time limit:	2 sec
Input file:	input.txt	Memory limit:	8 Mb
Output file:	output.txt

Statement

Text formatting functions (Format, sprintf, etc) are very common between programming languages. Your task is to implement a simplified one.

Formatting function receives format string and several arguments. Argument values are processed one by one and inserted into format string at positions designated by format specifiers. The following format specifiers must be implemented:

%s — argument as a string
%d — argument as an integer value, without any leading zeroes
%% — literal '%' character

Formatting error is generated if:

number of arguments required by format specifiers is not equal to the number of actually supplied arguments,
argument for %d specifier contains non-digit character.
'%' character in format string is not followed by either '%', 's' or 'd'.

Input file format

Input file contains format string followed by arguments, one per line.

Output file format

Output file must contain a single string — either formatted text or ERROR in case of any formatting error.

Constraints

Number of arguments is not greater than 1000, length of each line is not greater than 50000 characters.

Sample tests

No.	Input file (`input.txt`)	Output file (`output.txt`)
1	`%d x %d %s %d 2 02 = 4`	`2 x 2 = 4`
2	`%s`	`ERROR`
3	`%d 2a`	`ERROR`