Программа с переводом Char в Int и наоборот при переводе возвращает НИЧЕГО

#include <stdio.h>
#define INT_MIN -2147483648
#define INT_MAX 2147483647
 
int Char2Int(char string[]) {
    bool negative = false;
    int outputValue = 0;
    int stringLength = 0;
    while (string[stringLength] != '\0') {  // count the number of characters in the string
        stringLength++;
    }
    for (int i = 0; i < stringLength; i++) {
        if (string[i] == '-') {
            negative = true;  // remember that the input string is negative
        } else if (string[i] >= '0' && string[i] <= '9') {
            outputValue = outputValue * 10 + (string[i] - '0');  // convert the character to an integer and add it to the output value
        } else {
            return 0;  // return 0 if the input string is invalid
        }
    }
    if (negative) {
        outputValue *= -1;  // make the output value negative if necessary
    }
    return outputValue;
}
 
 
char* Int2Char(int inputNumber) {
    static char resultString[32];  // define the character array as a static local variable
 
    // Check that the input integer is within a valid range
    if (inputNumber < INT_MIN || inputNumber > INT_MAX) {
        return "";  // return an empty string if the input is out of range
    }
 
    // Handle the special case where the input integer is 0
    if (inputNumber == 0) {
        resultString[0] = '0';
        resultString[1] = '\0';
        return resultString;
    }
 
    // Convert the integer to a string
    int absoluteInputNumber;
    if (inputNumber < 0) {
        absoluteInputNumber = inputNumber * -1;  // take the absolute value of inputNumber
        resultString[0] = '-';  // add a minus sign to the beginning of the string
    } else {
        absoluteInputNumber = inputNumber;
    }
    int digit, reversedNumber = 0, resultIndex = 0;
    while (absoluteInputNumber > 0) {
        digit = absoluteInputNumber % 10;
        reversedNumber = reversedNumber * 10 + digit;
        absoluteInputNumber = absoluteInputNumber / 10;
    }
    while (reversedNumber > 0) {
        resultString[resultIndex + 1] = (reversedNumber % 10) + '0';  // start at resultIndex + 1 to skip the minus sign
        resultIndex++;
        reversedNumber = reversedNumber / 10;
    }
    resultString[resultIndex + 1] = '\0';  // add a null terminator to the end of the string
    return resultString;  // return a pointer to the character array
}
 
 
int main() {
    int inputNumber = 12345;
    printf("Integer: %d\n", inputNumber);
    printf("String: %s\n", Int2Char(inputNumber));
    int outputNumber = Char2Int(Int2Char(inputNumber));  // convert the string back to an integer
    printf("Output: %d\n", outputNumber);
    return 0;
}

resultString[resultIndex] = (reversedNumber % 10) + '0';

resultString[resultIndex] = (reversedNumber % 10) + '0';

................
 
    // Convert the integer to a string
    int absoluteInputNumber;
    int resultIndex = 0; /*FIX*/
    if (inputNumber < 0) {
        absoluteInputNumber = inputNumber * -1;  // take the absolute value of inputNumber
        /*FIX*/ resultString[resultIndex++] = '-';  // add a minus sign to the beginning of the string
 
    } else {
        absoluteInputNumber = inputNumber;
    }
    int digit, reversedNumber = 0;
    while (absoluteInputNumber > 0) {
        digit = absoluteInputNumber % 10;
        reversedNumber = reversedNumber * 10 + digit;
        absoluteInputNumber = absoluteInputNumber / 10;
    }
    while (reversedNumber > 0) {
        /*FIX*/ resultString[resultIndex] = (reversedNumber % 10) + '0';  // start at resultIndex + 1 to skip the minus sign
        resultIndex++;
        reversedNumber = reversedNumber / 10;
    }
    /*FIX*/ resultString[resultIndex] = '\0';  // add a null terminator to the end of the string
    return resultString;  // return a pointer to the character array
 
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