Go: package main

import "fmt"

func roundUp100(dept float64) float64 {
	iDept := int(dept)
	if iDept-(iDept/1000*1000) != 0 {
		iDept = ((iDept / 1000) + 1) * 1000
	}
	return float64(iDept)
}

func main() {
	var week int
	fmt.Scan(&week)

	dept := 100000.0
	for i := 0; i < week; i++ {

		dept *= 1.05
		dept = roundUp100(dept)
	}

	fmt.Println(dept)
}

C++: /*****include*****/
#include <iostream>
#include <fstream>

/*****デバッグ定義*****/
//#define DEBUG
/*****マクロ定義*****/

/*****名前空間*****/
using namespace std;

/*****グローバル変数置き場*****/

/*****その他関数置き場*****/

/*****main関数*****/
int main(){
	/*****ファイルオープン*****/
#ifdef DEBUG
	ofstream fout("output.txt");
	ifstream fin("input.txt");
	if(!fout || !fin){
		cout << "Can't open the file.\n";
		return;
	}
#endif
	/*****変数置き場*****/
	int year;
	long int money = 100000;
	/*****処理部*****/
	cin >> year;
	for(int i=1;i<=year;i++){
		money += money*0.05;
	}
	money /= 1000;
	if(money % 10 > 4){
		money /= 10;
		money++;
		money *= 10000;
	}else{
		money /= 10;
		money *= 10000;
	}
	cout << money << endl;
	/*****処理終了後*****/
#ifdef DEBUG
	fout.close();
	fin.close();
#endif
	return 0;
}

C++: #include <iostream>
#include <iomanip>
#include <cmath>

using namespace std;

int main()
{
    int week;
    cin >> week;

    double debt = 100;    // * 1000 yen
    while (week--) {
        debt = ceil(debt * 1.05);
    }

    cout << fixed << setprecision(0)
         << (debt * 1000) << endl;

    return 0;
}

C++: #include <iostream>
using namespace std;
int main( void )
{
  long long d=100000;
  int n;
  cin >> n;
  for( int i=0; i<n; i++ ){
    d += d/20;
    if( d % 1000 > 0 ) d = (d/1000+1)*1000;
  }
  cout << d << endl;
  return 0;
}

C++: #include<iostream>
#include<string>
#include<algorithm>
using namespace std;

int main(){
  int n;
  cin >>n;
  int sum=100000;
  int interest;
  for(int i =1 ; i<=n;i++){
    interest=sum*0.05;
    if (interest%1000>0)
    interest=(interest-interest%1000) + 1000;

    sum+= interest;
  }
  cout << sum;
}

C++: #include<iostream>
using namespace std;
int main(){
int n,ans=100000;
cin>>n;
while(int i=0;i<n;i++){
ans=ans*1.05;
if(ans%1000)ans=(ans\1000)*1000+1000;
}
cout<<ans<<endl;
return 0;
}

C++: #include <iostream>

using namespace std;

int main(void)
{
	int n;
	cin>>n;

	int money=100000;
	for(int i=0; i<n; i++){
		
		money = money*1.05;

		int amari;

		amari = money%1000;

		if(amari>0){
			money += amari = 1000-amari;
		}
	}
	cout<<money<<endl;
}