PHP Decode

<?  // Gib hier das Passwort ein (im Format flag{...}), welches du testen willst! Rohe Gewalt hilft hier nicht weiter. 
this.passwordInput = "flag{Nicht die Flag}"; 
 
let m=[true,null,115,112,108,105,116,14,108,101,110,103,116,104,102,205,291,394,511,600,633,787,878,918,1079,1115,1264,1310,1460,1576,1601,1759,1849,1888,2046,2089,2252,2283,2443,2524,2636,2668,2828,2929,2943,3132,112,97,115,115,119,111,114,100,73,110,112,117,116,116,111,83,116,114,105,110,103,24,99,104,97,114,67,111,100,101,65,116];m[1]=this[String.fromCharCode(a(46),a(47),a(48),a(49),a(50),a(51),a(52),a(53),a(54),a(55),a(56),a(57),a(58))][String.fromCharCode(a(2),a(3),a(4),a(5),a(6))]("");function a(i){return m[i];}for(let i=a(7);i<a(7)+this[String.fromCharCode(a(46),a(47),a(48),a(49),a(50),a(51),a(52),a(53),a(54),a(55),a(56),a(57),a(58))][String.fromCharCode(a(8),a(9),a(10),a(11),a(12),a(13))];i++){function c(o){if(a(1)[i-a(7)]!==String.fromCharCode(a(i)-(o*(i-a(7))))){m[0]=false;}}c(c[String.fromCharCode(a(59),a(60),a(61),a(62),a(63),a(64),a(65),a(66))]()[String.fromCharCode(a(68),a(69),a(70),a(71),a(72),a(73),a(74),a(75),a(76),a(77))](a(67)))};;; 
 
if (a(0)) { 
    console.log("Du hast die Challenge gelst!"); 
} else { 
    console.log("Leider falsch :(") 
} 
 ?>