C :

#include<stdio.h>
char* w(int n){
	char* t="";
	switch(n){
		case 0:t="ling";break;
		case 1:t="yi";break;
		case 2:t="er";break;
		case 3:t="san";break;
		case 4:t="si";break;
		case 5:t="wu";break;
		case 6:t="liu";break;
		case 7:t="qi";break;
		case 8:t="ba";break;
		default:t="jiu";
	}
	return t;
}
int main(){
	int n;
	scanf("%d",&n);
	if(n<=10){
		printf("%s",w(n));
	}else if(n<=19){
		printf("%s %s","shi",w(n%10));
	}else{
		printf("%s %s %s",w(n/10),"shi",w(n%10));
	}
	return 0;
}

C++ :

#include <bits/stdc++.h>
using namespace std;

void num(int n){
	if (n == 1){
		cout<<"yi";
	}else if (n == 2){
		cout<<"er";
	}else if (n == 3){
		cout<<"san";
	}else if (n == 4){
		cout<<"si";
	}else if (n == 5){
		cout<<"wu";
	}else if (n == 6){
		cout<<"liu";
	}else if (n == 7){
		cout<<"qi";
	}else if (n == 8){
		cout<<"ba"; 
	}else if (n == 9){
		cout<<"jiu";
	}else if (n == 0){
		cout<<"ling";
	}
}

int main(){
	int n,a,b;
	cin>>n;
	a = n / 10;
	b = n % 10;
	if (a == 0){
		num(b);
	}else{
		if (a == 1){
			if (b == 0){
				cout<<"shi";
			}else{
				cout<<"shi ";
				num(b);
			}
		}else{
			if (b == 0){
				num(a);
				cout<<" shi";
			}else{
				num(a);
				cout<<" shi ";
				num(b);
			}
		}
	}
}