#include<stdio.h>              //library of output and input functions
#include<conio.h>          //library of screen cleaning and other service
#include<math.h>             //library of mathematical functions
#include<iostream>
using namespace std;

void main()
{                  // main function - entry point to the programm
	  char simbol;
	  puts("function puts():");              //displaying the message on the screen
	  puts("input symbol");                 //displaying the message on the screen
	  putchar(getch());                  //output the symbol, what doesn't display during the entering
	  puts("\n repeat input symbol-function getch():");        //output the message
	  simbol=getch();                                        //input symbol from the keyboard
	  putchar(simbol);                                     //output symbol on the screen

	  char str[20];
	  puts("\n input string -function gets():");           //output te message on the screen

	  gets(str);                                            //input string
	  printf("functions printf(),puts(): str=");           //formatted output
	  puts(str);                                   //output string
	  printf("\r\n function printf(): str=%s \r\n",str);    //formatted output string

	  int i;
	  double a,b,c,d;

	  puts("function scanf(),printf()");
	  printf("\n input integer i, double a,b,c \n");                      // formatted output
      scanf("%i%d%d%d",&i,&a,&b,&c);                                   //formatted input
	  printf("i=%i a=%d b=%d c=%d", i,a,b,c);                         //formatted output
	  puts("\n input string for sscanf() as %d %f %f or sprintf()");

	  char str1[40],str2[40];
	  float a1,b1;
	  fflush(stdin);             // cleaning the keyboard buffer

	  gets(str1);                    //input string from keyboard
	  printf("string is: ");
	  puts(str1);
	  sscanf(str1,"&d %f %f", &i, &a1, &b1);        // input from string to the addresses of variables
	  printf("i=%i a=%f b=%e\n",i,a1,b1);                //output on the screen
	  puts("function sprintf() does not display rezult");
	  sprintf(str2,"i=%d a=%f b=%e",i,a1,b1);            // output into the string
	  puts("function puts():");
	  puts(str2);
	  d=(a-abs(a/b))/(2.75*sin(c)*sin(c));//calculating the expression
	  puts("function printf():");
	  printf("d=(a-abs(a/b)/2.75*pow(sin(c),2)=%d",d);

	  char string[30];                                  //announce the string

	  cout<<"\n input text"<<endl;
	  cin>>string;
	  cout<<"entered text is"<<"'"<<string<<"'"<<endl;
	  fflush(stdin);
	  getch();                                         //delay screen

}