---

data_process.c:
#include "data_process.h"
#include <math.h>

int normalization(double *data, int n)
{
    int result = 1;
    double max_value = max(data, n);
    double min_value = min(data, n);
    double size = max_value - min_value;

    if(fabs(size) < EPS)
    {
        for (int i = 0; i < n; i++)
        {
            data[i] = data[i] / size - min_value / size;
        }
    }
    else
    {
        result = 0;
    }
    
    return result;
}
data_io.h:
#ifndef DATA_IO_H
#define DATA_IO_H

void input(double *data, int n);
void output(double *data, int n);

#endif

data_io.c:
#include "data_io.h"

data_stat.h:
#ifndef DATA_STAT_H
#define DATA_STAT_H

double max(double *data, int n);
double min(double *data, int n);
double mean(double *data, int n);
double variance(double *data, int n);

#endif

data_stat.c:
#include "data_stat.h"