C:

#include<stdio.h>

int main(){

int n;

scanf("%d",&n);

printrf("%d\n", n-1);

return 0;

}

-----------------------------------------------------------------------------------

C++:

#include<iostream>

using namespace std;

int main(){

int n;

cin>>n;

cout<<n-1<<endl;

return 0;

}

-----------------------------------------------------------------------------------

Java:

public class Java{

public static void main(String[] args){

System.out.println(new java.util.Scanner(System.in).nextInt()-1);

}

}

------------------------------------------------------------------------------------

Python:

print(int(input())-1)

===============================================

C/C++如果有更短的寫法歡迎分享，Java跟Python應該已經是最短了~