media/variancia/dp usando alocação

# include <stdio.h>
# include <stdlib.h>
# include <math.h>
float media(int n, float *v);
float variancia(int n, float *v, float md);

int main(void)
{
int n, i;
float *v, var, md, dp;
printf("digite o numero de notas\n");
scanf("%d", &n);
v=(float *)malloc(n*sizeof(float));
for(i=0;i<n;i++){
printf("digite valor\n");
scanf("%f", &v[i]);
}
md=media(n,v);
printf("media=%f\n", md);
var=variancia(n,v,md);
printf("variancia=%f\n", var);
dp=sqrt(var);
printf("desvio p=%f\n", dp);
system("pause");
return 0;
}

float media(int n, float *v)
{
int i;
float m=0.0;
for(i=0;i<n;i++){
m=m+v[i];
}
m=m/n;
return m;
}

float variancia(int n, float *v, float m)
{
int i;
float var=0.0;
for(i=0;i<n;i++){
var=var+(v[i]-m)*(v[i]-m);
}
var=var/(n-1);
return var;
}