[C language] Up-down game strategy experiment program error (only 0 appears)

#include <stdio.h>
int number = 100;
int answer = 450;
int numberplus = 0;
int true;
int count = 0;
int minnumber = 100;
int maxnumber = 999;
int numbercount = 0;
int buffer;
main()
{
    while (!numbercount == 900)
    {
        while (!number == answer)
        {
            check();
            Compare answer and number.
            makeanswer();
            Make a new answer.
        } //If number and answer are the same at this time, it ends.

        printf("%d", count);
        //Insert count into list.
        clear();
        //Initialize the variable.
        makeanswer;
        Make a new answer with a new value.
    }// The number count ends at 899.
    //printf("%d", numberplus);
    //printf("%f\n", numberplus / 899);
}
/*********************************************************/
int check(void)
{
    if (number > answer)
        {
            true = 0;
            count++;
        }
    else if (number < answer)
        {
            true = 1;
            count++;
        }
    return (true);
}
/***********************************************************/
int makeanswer(void)
{
    if (true == 0)
    {
        buffer = (maxnumber - answer) / 2;
        maxnumber = answer;
        answer = buffer;
    }
    else if (true == 1)
    {
        buffer = (answer - minnumber) / 2;
        minnumber = answer;
        answer = buffer;
    }
    return (true);
}
/***********************************************************/
int clear(void)
{
    true = 0;
    count = 0;
    minnumber = 100;
    maxnumber = 999;
    numbercount++;
    number++;
}