#include<iostream.h>
#include<conio.h>
#include<string.h>
char strng[50];
int len, n;
void cmpltcnvrsion(char strng[50])
{
for(int i=0 ; i<len ; i++)
{
if((97<=int(strng[i]))&&(int(strng[i])<=122))
cout<<char(int(strng[i])-32);
else if((65<=int(strng[i]))&&(int(strng[i])<=90))
cout<<char(int(strng[i])+32);
else
cout<<strng[i];
}
}
void capital(char strng[50])
{
for(int i=0 ; i<len ; i++)
{
if((97<=int(strng[i]))&&(int(strng[i])<=122))
cout<<char(int(strng[i])-32);
else
cout<<strng[i];
}
}
void small(char strng[50])
{
for(int i=0 ; i<len ; i++)
{
if((65<=int(strng[i]))&&(int(strng[i])<=90))
cout<<char(int(strng[i])+32);
else
cout<<strng[i];
}
}
void main()
{
clrscr();
cout<<"Enter a string :\n";
cin.getline(strng,50);
len=strlen(strng);
cout<<"\n\nChoose the type of conversion : \n 1>Complete conversion \n 2>ALL CAPITAL \n 3>all small \nEnter your choice : ";
cin>>n;
switch(n)
{
case 1 : cmpltcnvrsion(strng);
break;
case 2 : capital(strng);
break;
case 3 : small(strng);
break;
}
getch();
}
.................................................................
OUTPUT: (click to enlarge the image)