C program to calculate standard deviation

				
					#include<stdio.h>
#include<conio.h>
#include<math.h> 
#define MAX 100 
void main()
{
int i, n;
float val [MAX], deviation;
sum=0;
sumsq=0;
n=0;
printf(“Input values: input -1 to end”);
for(i=1; i<MAX; i++)
{
scanf(“%f”, &val[i]);
if(val[i]= =-1)
break; 
sum+=val[i]; n+=1;
}
mean=sum/(float)n; 
for(i=1; i<=n; i++)
{
deviation=val[i]-mean;
sumsq+=deviation* deviation;
}
variance=sumsq/(float)n; 
stddeviation=sqrt(variance); 
printf(“Number of items: %d”, n); 
printf(“Mean: %f”,mean);
printf(“Standard deviation:%f”, stddeviation);
}

				
			
Output:

Input values: input -1 to end 

65 9 27 78 12 20 33 49 -1

Number of items: 8 

Mean: 36.625000

Standard deviation: 23.510303

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