10.c

/*
Write a function to accept a sequence of real number,
Find the mean,median, variance and standard deviation of the sequence.
*/
#include <stdio.h>
#include <stdlib.h>
#include <math.h>
int main()
{
    float *x, mean = 0, median, sd = 0, var = 0;
    int n, i, j, temp;
    printf("Enter the no of entries:");
    scanf("%d", &n);
    x = (float *)malloc(sizeof(float) * n);

    printf("Enter your inputs:\n");
    for (i = 0; i < n; i++)
        scanf("%f", &x[i]);

    for (i = 0; i < n; i++)    //calc mean
        mean = mean + x[i];
    mean = mean / n;

    for (i = 0; i < n; i++)    // calc var
        var = var + pow((x[i] - mean), 2);

    var = var / n;

    sd = sqrt(var);            // calc sd

    for (i = 0; i < n - 1; i++)    //shorting for median
        for (j = i; j < n; j++)
        {
            if (x[i] > x[j])
            {
                temp = x[i];
                x[i] = x[j];
                x[j] = temp;
            }
        }

    if ((n + 1) % 2 == 0)     // calc median
    {
        median = x[((n + 1) / 2) - 1];
    }
    else
    {
        median = (x[((n + 1) / 2) - 1] + x[((n + 2) / 2) - 1]) / 2;
    }

    printf("Mean : %f\n", mean);
    printf("Median: %f\n", median);
    printf("Variance: %f\n", var);
    printf("Standard deviation: %f\n", sd);

    return 0;
}