Choice of entering marks::

#include<conio.h>

#include<stdio.h>

void main()

{

int a[10],i,n,m,d;

float b;

printf("\n 1.input \n 2.output \n 3.highest marks \n 4.lowest marks \n 5.mean of the marks");

printf("\n\n Enter your choice:");

scanf("%d",&d);

switch(d)

{case 1:

n=1;

for(i=0;i<=9;i++)

{printf("\n %d.",n);

scanf("%d",&a[i]);

n++;}

break;

case 2:

n=1;

for(i=0;i<=9;i++)

{printf("\n %d.",n);

printf("%d",a[i]);

n++;}

break;

case 3:

printf("\n \n calculation of highest marks");

m=a[0];

for(i=0;i<=9;i++)

{if(m<a[i])

m=a[i];}

printf("\n %d",m);

break;

case 4:

printf("\n \n calculation for lowest marks");

m=a[0];

for(i=0;i<=10;i++)

{if(m>a[i])

m=a[i];}

printf("\n %d",m);

break;

case 5:

printf("\n \n calculation of mean of the marks");

m=0;

for(i=0;i<=9;i++)

{m=m+a[i];}

b=m/10;

printf("\n %f",b);

break;

default:("not match");

                                       }

getch();}