Programas estructura de datos informatica

/*programa de base de datos*/
#include <stdio.h>
#include <conio.h>
main ()
{
char tecla;
printf("TIPOS base de C.\n\n\n");
printf("TIPO char\t\t=>\t%d bytes\n\n",sizeof(char));
printf("TIPO unsigned char\t=>\t%d bytes\n\n", sizeof(unsigned char));
printf("TIPO short\t\t=>\t%d bytes\n\n", sizeof(short));
printf("TIPO int\t\t=>\t%dbytes\n\n", sizeof(int));
printf("TIPO unsigned int\t=>\t%d bytes\n\n", sizeof(unsigned int));
printf("TIPO long\t\t=>\t%d bytes\n\n", sizeof(long));
printf("TIPO unsignedlong\t=>\t%d bytes\n\n", sizeof(unsigned long));
printf("TIPO float\t\t=>\t%d bytes\n\n", sizeof(float));
printf("TIPO double\t\t=>\t%d bytes\n\n", sizeof(double));
printf("TIPO longdouble\t=>\t%d bytes\n\n", sizeof(long double));
tecla = getch();
}

#include <cstdlib>
#include <iostream>
using namespace std;
int main(int argc, char *argv[])
//programa de l 35al 92//
{ int i ; char pausa;
for (i=35;i<=92;i=i+3)
{ printf ("valor de i:%d\n",i);
}
system("PAUSE");
return EXIT_SUCCESS;
}

/* programa de pi*/
#include <stdio.h>#include <conio.h>
int main()
{
float pi;
char tecla;
pi = 3.1415926535;
printf("EL VALOR DE PI ES: %f\n\n", pi);
printf("EL VALOR DE PI CON DOS DECIMALES ES: %4.f\n\n",pi);
printf("EL VALOR DE PI CON CUATRO DECIMALES ES: %5.f\n\n", pi);
tecla = getch();
}

/*programa que imprima hola mundo*/
#include <stdio.h>
#include <conio.h>
int main()
{
int a,b;
char tecla;
a = 5;
b = 10;

printf("HOLA MUNDO \n\n\n");
printf("valor de a:\t%d\n\nalor de b:\t%d\n\n\n", a,b);
tecla = getch();
}

#include<stdio.h>
#include <conio.h>
int main ()
{
int x;
float y;
char c, tecla;
printf("introduce un valor entero x:");
scanf ("%d",&x);
printf ("introduce...