CHECK BALANCED EXPRESSION USING STACK

/* check balanced  expression using stack */

#include < stdio.h >

#include < conio.h >

#define max 50

void main()

{

                char stk[max],exp[100];

                int top,i;              

                clrscr();

                top = -1;              

                printf("\nEnter an infix expression ");

                gets(exp);          

                for(i=0; exp[i] != '\0'; i++)

                {

                                if( exp[i]=='(' || exp[i] =='[' || exp[i] == '{' )

                                {

                                                top++;

                                                stk[top]= exp[i];

                                }

                                else

                                if ( exp[i] == ')' )

                                {

                                                if( stk[top] == '(' )

                                                top--;

                                }

                                else

                                {

                                                printf("Unbalanced exp");

                                                exit(0);

                                }

                                }

                                else

                                if ( exp[i] == ']' )

                                {

                                if( stk[top] == '[' )

                                                top--;

                                else

                                {

                                                printf("Unbalanced exp");

                                                exit(0);

                                }

                                }

                                else

                                if ( exp[i] == '}' )

                                {

                                if( stk[top] == '{' )

                                                top--;

                                else

                                {

                                                printf("Unbalanced exp");

                                                exit(0);

                                }

                                }

                } // for

                if( top == -1 )

                                printf("Exp is balanced");

                else

                                printf("Exp is not balanced");

} 

AVERAGE OF N NUMBERS

/* Average Of N Numbers */

#include < stdio.h >

#include < conio.h >

void main()

{

                float a[20],sum,avg;

                int n,i;

                clrscr();

                printf("\nEnter n : ");

                scanf("%d", &n);

                printf("\nEnter %d numbers \n",n);

                for(i=0;i < n;i++)

                {

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

                }

                sum = 0;

                for(i=0;i < n;i++)

                {

                                sum += a[i];

                }

                avg = sum / n;

                printf("\nEntered %d numbers are \n",n);

                for(i=0;i < n;i++)

                {

                                printf("\n%.2f",a[i]);

                }

                printf("\nThe average of numbers is %f",avg);

}