Permutation_sequence_With_case_change.cpp

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

void solve(string ip ,string op){
	if(ip.size() == 0){
		cout<<op<<" ";
		return;
	}

	string op1 = op;
	string op2 = op;

	op1.push_back(ip[0]);
	op2.push_back(toupper(ip[0]));
	ip.erase(ip.begin() + 0);
	solve(ip,op1);
	solve(ip,op2);
}

int main(){
	string ip = "ab";
	string op = "";
	solve(ip,op);
}