# Number system conversion in C++

By kamayani

• c++ number system conversion.txt
• conversion_system.sln
• In this C++ code, we can convert the given number from- 1) binary to hexadecimal 2) decimal to octal 3) decimal to hexadecimal 4) octal to binary

This code allows users to convert given input numbers to different number systems by giving a list of conversion options.

we are using different functions and switch cases. The main part of the program asks for all the input and it will call that respective function to carry out the further process as per the user's demand.

CODE-

```#include

#include

#include

using namespace std;
void hex(int num) {
int i, temp = 0, hexa[20], rem;
cout << "Hexadecimal eqivalent ";
for (i = 0; num > 0; i++) {
for (int y = 0; y < 4; y++) {
rem = num % 10;
num /= 10;
temp += rem * pow(2, y);
}
hexa[i] = temp;
temp = 0;
}
while (i > 0) {
i--;
if (hexa[i] > 9)
cout << char(55 + hexa[i]);
else
cout << hexa[i];
}
}
void oct(int n) {
int a[20], i;
for (i = 0; n != 0; i++) {
a[i] = n % 8;
n = n / 8;
}
for (int y = i - 1; y >= 0; y--)
cout << a[y];
}
void hexn(int num) {
int hexa[20], i;
for (i = 0; num > 0; i++) {
hexa[i] = num % 16;
num /= 16;
}
while (i > 0) {
i--;
if (hexa[i] > 9)
cout << char(55 + hexa[i]);
else
cout << hexa[i];
}
}
void bin(int num) {
int binary = 0, rem, temp = 1, z = 1;
cout << "Binary equivalent = ";
while (num > 0) {
temp = num % 10;
num /= 10;
for (int y = 0; y < 3; y++) {
rem = temp % 2;
temp /= 2;
binary += rem * z;
z *= 10;
}
}
cout << binary;
}

int main() {
char input;
while (1) {
cout<<"\t\t\t\t\t\t Number system conversion \t\t\t\t\t\t";
cout << ("\nEnter the input character and q to quit.\n  1. binary to hexadecimal\n  2. decimal to octal\n  3. decimal to hexadecimal\n  4. octal to binary\n ");
cin >> input;

switch (input) {
case 'q':
cout << ("Quitting the program...");
goto end;
break;

case '1':
int num;
cout << "Enter the number in binary ";
cin >> num;
hex(num);
break;

case '2':
int n;
cout << "Enter number : ";
cin >> n;
cout << "Octal equivalent : ";
oct(n);
break;
case '3':
int numb;
cout << "Enter number : ";
cin >> numb;
cout << "Hexadecimal equivalent : ";
hexn(numb);
break;
case '4':
int number;
cout << "Enter the number in octal ";
cin >> number;
bin(number);
break;
default:
cout << ("In default now");
break;
}
}
end:

return 0;
}```

OUTPUT-