Index calculation C++

Index calculation

July 1st is the founding day of the party. From 1921 to 2020, the Communist Party of China has led the Chinese people through 99 years.
Please calculate: 7 ^ 2020 mod 1921, where A mod B represents the remainder of A divided by B.

#include <iostream>
using namespace std;

//递归求解
int power(int b, int p, int s){
    
    
	if(p != 0)
		return (b*power(b,p-1,s)%s);
	else
		return 1;
}

int main(){
    
    
	int b,p,s,res;	//b为基数，P为指数，s为取余 
	cin >> b >> p >>s;
	
	res = power(b,p,s);
	
	cout << res; 
	return 0;
}