C Program to get mean ,median ,mode

#include
#include
#include

float mean1(float[],int);
float median1(float[],int);
float mode1(float[],int);
double standarddeviation1(float[],int);

int main()
{
    int i,n,choice;
    float array[100],mean,median,mode;
    double standarddeviation;
    printf("Enter No of Elements\n");
    scanf("%d",&n);
    printf("Enter Elements\n");
    for(i=0;i<=n;i++)
        scanf("%f",&array[i]);
do
{
    printf("\n\tEnter Choice\n\t1.Mean\n\t2.Median\n\t3.Mode\n\t4.Standard deviation\n\t5.Exit\n");
    scanf("%d",&choice);
    switch(choice)
    {
     case 1: mean=mean1(array,n);
             printf("\n\tMean = %f\n",mean);
             break;
     case 2: median=median1(array,n);
             printf("\n\tMedian = %f\n",median);
             break;
     case 3: mode=mode1(array,n);
             printf("\n\tMode = %f\n",mode);
             break;
     case 4: standarddeviation=standarddeviation1(array,n);
             printf("\n\tStandard deviation = %f\n",standarddeviation);
             break;
     case 5: break;
             default:printf("Wrong Option");
             break;
     }
}while(choice!=5);
getch();
return 0;
}

float mean1(float array[],int n)
{
      int i;
      float sum=0;
      for(i=0;i<=n;i++)
      sum=sum+array[i];
      return (sum/n);
}
float median1(float array[],int n)
{
      float temp;
      int i,j;
      for(i=n-1;i=>0;i--)
      {
             for(j=0;j<=i;j++)
             {
                 if(array[j]>=array[j+1])
                 {
                 temp=array[j];
                 array[j]=array[j+1];
                 array[j+1]=temp;
                 }
             }
      }
      if(n%2==0)
      return (array[n/2]+array[n/2-1])/2;
      else
      return array[n/2];
}

float mode1(float array[],int n)
      {
      return (3*median1(array,n)-2*mean1(array,n));
      }

double standarddeviation1(float array[],int n)
{
      int j; 
      double max[100],sum,variance,mean;
      mean=mean1(array,n);
      sum=0;
      for(j=0;j<=n;j++) 
      {
         max[j]=pow((array[j]-mean),2);
         sum+=max[j];
      }
      variance=sum/(j-1); 
      return sqrt(variance);
}