# C++ Program to Check Whether a Number is Unique Number or Not

A unique number is a number in which no digit is repeated. For example: 102452 is not a unique number as 2 is repeated twice while 2374 is a unique number. So in this article I am sharing the C++ program that check if a number is unique or not.

```#include<iostream>
#include<stdlib.h>

using namespace std;

int main()
{
long num;
char str[10];
int a[10]={0},flag=1,i=0;

cout<<"Enter any number:";
cin>>num;
itoa(num,str,10);	//convert number to character array

while(str[i]!='\0')
{
switch(str[i])
{
case '0':
a[0]++;
break;
case '1':
a[1]++;
break;
case '2':
a[2]++;
break;
case '3':
a[3]++;
break;
case '4':
a[4]++;
break;
case '5':
a[5]++;
break;
case '6':
a[6]++;
break;
case '7':
a[7]++;
break;
case '8':
a[8]++;
break;
case '9':
a[9]++;
break;
}
i++;
}

for(i=0;i<10;i++)
{
if(a[i]>1)
{
flag=0;
break;
}
}

if(flag)
cout<<"\nNumber is Unique";
else
cout<<"\nNumber is Not Unique";

return 0;
}```
Output
If you have any other solution for this problem then you can share it with us by commenting below.

### 4 thoughts on “C++ Program to Check Whether a Number is Unique Number or Not”

1. You could just sort this string, and check with one for(). Like this:

#include
#include
#include

int main() {
char num[100];
scanf("%s", num); // read number as string
int len = strlen(num);
std::sort(num, num+len); // sort string
for (int i = 1; i < len; i++) {
if (num[i-1] == num[i]) {
printf("nNumber is Not Unique");
return 0;
}
}
printf("nNumber is Unique");
return 0;
}

2. József Kerékgyártó

I just did it. Hope you like it 🙂

bool is_unique_number(char * snumber) {
for (int j = 0; j <= 9; j++) {
int counter = 0;
for (int i = 0; snumber[i] != ''; i++)
if ((snumber[i] – '0') == j)
counter++;
if (counter > 1)
return false;
}
return true;
}

3. Please start a YouTube channel for breif knowledge…. Some of the starting programmers like me had to face a lot of difficulty in understanding!