CALCULATOR

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

#define lengthOfString 100

typedef struct operand_s operand_s;
struct operand_s
{
    double theOperand;
    char theOperator;
    int theDegree;
    operand_s *nextOperand;
};

void intialization_operands(operand_s *myOperands, int nbrOperands)
{
    for (int i = 0; i < nbrOperands; i++)
    {
        operand_s *newOperand = malloc(sizeof(*newOperand));
        newOperand->theOperand = 0;
        newOperand->theOperator = ' ';
        newOperand->theDegree = 0;
        newOperand->nextOperand = myOperands->nextOperand;
        myOperands->nextOperand = newOperand;
    }
}

int nmbrOfDigInOper(char *myOperation)
{
    int theNumbre = 0;
    for (int i = 0; myOperation[i] != '\0'; i++)
    {
        if (myOperation[i] >= 48 && myOperation[i] <= 57)
        {
            theNumbre++;
            while (myOperation[i] >= 48 && myOperation[i] <= 57 || myOperation[i] == '.')
            {
                i++;
            }
        }
    }
    return theNumbre;
}

int first_treatment(char *myOperation, operand_s *myOperands)
{
    int degree = 0, largDegree = 0;

    operand_s *temporaryOp = myOperands;

    for (int i = 0; myOperation[i] != '\0'; i++)
    {
        if (myOperation[i] == '(')
        {
            degree += 2;
            if (degree > largDegree)
                largDegree = degree;
        }
        else if (myOperation[i] == ')')
        {
            degree -= 2;
            temporaryOp->theDegree -= 2;
        }
        else if (myOperation[i] >= 48 && myOperation[i] <= 57)
        {
            temporaryOp->theDegree = degree;
            temporaryOp->theOperand = strtod(&myOperation[i], NULL);
            if (myOperation[i - 2] == '(')
                temporaryOp->theOperand *= -1;
            while (myOperation[i] >= 48 && myOperation[i] <= 57 || myOperation[i] == '.')
            {
                i++;
            }
            i--;

        }
        else if (myOperation[i] == '*' || myOperation[i] == '/')
        {
            temporaryOp->theDegree++;
            if (temporaryOp->theDegree > largDegree)
                largDegree = temporaryOp->theDegree;
            temporaryOp->theOperator = myOperation[i];
            temporaryOp = temporaryOp->nextOperand;
        }
        else if (myOperation[i] == '+' || myOperation[i] == '-')
        {
            if (myOperation[i - 1] != '(')
            {
                temporaryOp->theOperator = myOperation[i];
                temporaryOp = temporaryOp->nextOperand;
            }
        }

    }
    return largDegree;
}

void second_treatment(operand_s *myOperands, int largDegree)
{
    operand_s *temporaryOp = myOperands, *operandADelet = NULL;
    while (temporaryOp->nextOperand != NULL)
    {
        if (temporaryOp->theDegree == largDegree)
        {
            switch (temporaryOp->theOperator)
            {
            case '*':
                temporaryOp->theOperand *= temporaryOp->nextOperand->theOperand;
                break;
            case '/':
                temporaryOp->theOperand /= temporaryOp->nextOperand->theOperand;
                break;
            case '+':
                temporaryOp->theOperand += temporaryOp->nextOperand->theOperand;
                break;
            case '-':
                temporaryOp->theOperand -= temporaryOp->nextOperand->theOperand;
                break;
            }
            temporaryOp->theOperator = temporaryOp->nextOperand->theOperator;
            temporaryOp->theDegree = temporaryOp->nextOperand->theDegree;
            operandADelet = temporaryOp->nextOperand;
            temporaryOp->nextOperand = temporaryOp->nextOperand->nextOperand;
            free(operandADelet);
        }
        else if (temporaryOp->theDegree != largDegree)
            temporaryOp = temporaryOp->nextOperand;
    }
}

int main()
{
    int nmbrOfDig, largDegree;
    char theOperation[lengthOfString] = { ' ' };
    operand_s *theOperands = malloc(sizeof(*theOperands));

    theOperands->theOperand = 0;
    theOperands->theOperator = ' ';
    theOperands->theDegree = 0;
    theOperands->nextOperand = NULL;

    scanf("%s", theOperation);

    nmbrOfDig = nmbrOfDigInOper((char*)&theOperation);
    intialization_operands(theOperands, nmbrOfDig - 1);
    largDegree = first_treatment((char*)&theOperation, theOperands);

    while (largDegree >= 0)
    {
        second_treatment(theOperands, largDegree);
        largDegree--;
    }

    printf("%s = %lf\n", theOperation, theOperands->theOperand);

    free(theOperands);
    return 0;
}