[HackerRank] Staircase c++

• problem

This is a staircase of size n =4 :

   #
  ##
 ###
####

Its base and height are both equal to n. It is drawn using # symbols and spaces. The last line is not preceded by any spaces.

Write a program that prints a staircase of size n.

 

• sample input

6 

• sample output

     #
    ##
   ###
  ####
 #####
######

 

• explanation

The staircase is right-aligned, composed of # symbols and spaces, and has a height and width of n = 6.

 

• solution

void staircase(int n) {
    string res("");
    for(int i = 0; i < n; i++){
        string s("");
        for(int j = 0; j < n-i -1; j++ ){
            s += " ";
        }
        for(int j = n-i -1; j < n; j++){
            s += "#";
        }
        res += s + "\n";
    }
    cout << res;
}