number-converter/Main.c

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

typedef unsigned int uint;
typedef char* string;

uint getNumberOfDigits(uint number) {
    uint counter = 1;
    while(number >= 10) {
        number /= 10;
        counter++;
    }
    return counter;
}

int convertNumberToDigits(uint number, char* buffer, uint bufferLength, const string* digits, uint dWidth, uint dHeight) {
    uint digitAmount = getNumberOfDigits(number);
    uint lineLength = digitAmount * dWidth + 1;
    uint length = lineLength * dHeight;
    if(length >= bufferLength) {
        return 1;
    }
    for(uint i = 0; i < digitAmount; i++) {
        uint digit = number % 10;
        uint offset = (digitAmount - 1 - i) * dWidth;
        for(uint line = 0; line < dHeight; line++) {
            memcpy(buffer + offset + lineLength * line, digits[digit] + dWidth * line, dWidth);
        }
        number /= 10;
    }
    for(uint line = 1; line < dHeight; line++) {
        buffer[lineLength * line - 1] = '\n';
    }
    buffer[length - 1] = '\0';
    return 0;
}

int convertNumber(uint number, char* buffer, uint bufferLength) {
    const string digits[] = {"0", "1", "2", "3", "4", "5", "6", "7", "8", "9"};
    return convertNumberToDigits(number, buffer, bufferLength, digits, 1, 1);
}

void printSmallDigits(uint number) {
    char buffer[128];
    if(convertNumber(number, buffer, 128)) {
        return;
    }
    puts(buffer);
}

void printBigDigits(uint number) {
    const uint digitWidth = 3;
    const uint digitHeight = 3;
    const string digits[] = {
        " _ | ||_|", // 0
        "     |  |", // 1
        " _  _||_ ", // 2
        " _  _| _|", // 3
        "   |_|  |", // 4
        " _ |_  _|", // 5
        " _ |_ |_|", // 6
        " _   |  |", // 7
        " _ |_||_|", // 8
        " _ |_| _|" //  9
    };

    char buffer[128];
    if(convertNumberToDigits(number, buffer, 128, digits, digitWidth, digitHeight)) {
        return;
    }
    puts(buffer);
}

int main() {
    printSmallDigits(1234567890);
    printBigDigits(1234567890);
    return EXIT_SUCCESS;
}