update for cleaner code

install.sh

@@ -1,6 +1,5 @@
-#!/bin/bash
+#!/usr/bin/env bash
 
-# get operating system
 install_packages() {
   declare -A osInfo;
   osInfo[/usr/bin/pacman]=pacman
@@ -11,10 +10,10 @@ install_packages() {
   do
     if [[ -f $f ]];then
       if [[ ${osInfo[$f]} == 'pacman' ]]; then
-        pacman -S clang make cmake fltk catch2
+        sudo pacman -S clang make cmake fltk catch2
 
       elif [[ ${osInfo[$f]} == 'apt' ]]; then
-        apt install clang make cmake clang-tidy libfltk1.3 libfltk1.3-dev
+        sudo apt install clang make cmake clang-tidy libfltk1.3 libfltk1.3-dev
 
         git clone https://github.com/catchorg/Catch2.git
         cd Catch2
@@ -22,7 +21,7 @@ install_packages() {
         sudo cmake --build build/ --target install
 
       elif [[ ${osInfo[$f]} == 'brew' ]]; then
-        brew install llvm clang make cmake clang-format fltk catch2
+        sudo brew install llvm clang make cmake clang-format fltk catch2
         
       fi
     fi
@@ -59,4 +58,4 @@ mkdir demo/build
 cd installation
 
 echo "installation completed"
-./build.sh
+./build.sh