M-ary to n-ary

Blog for the first time , Record the questions you usually do , In order to review and use in the future

This is a binary conversion problem , The code is as follows ：

because 0-Z Only 36 Characters , So this question can only be in 36 Conversion within hexadecimal
The idea is to M Convert hexadecimal digits to decimal , Then convert the decimal system to N Base number

#include<iostream>
#include<string>
using namespace std;
void convert_MtoN(string a,int M,int N)
{
    
	long long temp=0;
	for(int i=0;i<a.length();i++)// First the a Convert to 10 Hexadecimal number  
	{
    
		if(a[i]>='A' && a[i]<='Z')
		{
    
			temp*=M;
			temp+=a[i]-'A'+10;
		}
		else if(a[i]>='0' && a[i]<='9')
		{
    
			temp*=M;
			temp+=a[i]-'0';
		}
		else
		{
    
			cout<<" Illegal input ！\n";
			return;
		}
	}
	if(N==10)// If it is converted to decimal, it will be output directly 
		cout<<temp;
	else
	{
    
		if(temp==0)
			cout<<0;
		string b=""; 
		int n=0;// Record the number of digits 
		while(temp>0)
		{
    
			b+=char(temp%N+'0');
			temp/=N;
			n++;
		}
		for(int i=n-1;i>=0;i--)
		{
    
			if(b[i]>'9')
				cout<<char(b[i]-10+'A');
			else
				cout<<b[i];
		}
	}
		
}
int main()
{
    
	// Example 
	string a="CAIXUKUN666";
	//cin>>a;
	convert_MtoN(a,36,10);
	return 0;
}