TheAlgorithms-C/leetcode/src/8.c

int myAtoi(char *str)
{
    int minusFlag = 0;
    int length = strlen(str);
    long int result = 0;
    char numberBuffer[11];
    int counter = 0;
    while (str[counter] == ' ')
    {
        counter++;
    }
    str = &str[counter];
    counter = 0;

    for (int i = 0; i < length; i++)
    {
        if (i == 0)
        {
            if (str[0] == '-')
            {
                minusFlag = 1;
                i++;
            }
            else if (str[0] == '+')
            {
                i++;
            }
        }
        if (counter > 10)
        {
            if (minusFlag)
            {
                return __INT_MAX__ * -1 - 1;
            }
            else
            {
                return __INT_MAX__;
            }
        }

        if (str[i] < '0' || str[i] > '9')
        {
            break;
        }
        if (counter == 0 && str[i] == '0')
        {
            continue;
        }

        numberBuffer[counter] = str[i];
        counter++;
    }

    int i = 0;
    while (counter > 0)
    {
        if (minusFlag)
        {
            result -= (numberBuffer[i] - '0') * pow(10.0, counter - 1);
        }
        else
        {
            result += (numberBuffer[i] - '0') * pow(10.0, counter - 1);
        }
        i++;
        counter--;
    }

    if (result > __INT_MAX__)
    {
        return __INT_MAX__;
    }
    else if (result < __INT_MAX__ * -1 - 1)
    {
        return __INT_MAX__ * -1 - 1;
    }
    return result;
}