javascript - Array.sort working differently in chrome and firefox and IE

Question

I'm trying to sort an array that contains objects, based on the field[marks] in the object. The array is getting sorted differently in Firefox and chrome. In Chrome and IE9 the sixteenth item gets shifted to the top of the array for no reason. Since all the marks are 0 I assumed no sorting will take place. No sorting happens in Firefox but that's not the case with chrome and IE. Please find the code below I have used. Any advice to why this happens would be much appreciated

var arr = [
{"userid":"1","name":"USER_1","subjectid":"123","marks":"0"},
{"userid":"2","name":"USER_2","subjectid":"123","marks":"0"},
{"userid":"3","name":"USER_3","subjectid":"123","marks":"0"},
{"userid":"4","name":"USER_4","subjectid":"123","marks":"0"},
{"userid":"5","name":"USER_5","subjectid":"123","marks":"0"},
{"userid":"6","name":"USER_6 ","subjectid":"123","marks":"0"},
{"userid":"7","name":"USER_7","subjectid":"123","marks":"0"},
{"userid":"8","name":"USER_8","subjectid":"123","marks":"0"},
{"userid":"9","name":"USER_9","subjectid":"123","marks":"0"},
{"userid":"10","name":"USER_10","subjectid":"123","marks":"0"},
{"userid":"11","name":"USER_11","subjectid":"123","marks":"0"},
{"userid":"12","name":"USER_12","subjectid":"123","marks":"0"},
{"userid":"13","name":"USER_13","subjectid":"123","marks":"0"},
{"userid":"14","name":"USER_14","subjectid":"123","marks":"0"},
{"userid":"15","name":"USER_15","subjectid":"123","marks":"0"},
{"userid":"16","name":"USER_6","subjectid":"123","marks":"0"},
{"userid":"17","name":"USER_17","subjectid":"123","marks":"0"},
{"userid":"18","name":"USER_8","subjectid":"123","marks":"0"},
{"userid":"19","name":"USER_19","subjectid":"123","marks":"0"},
{"userid":"20","name":"USER_20","subjectid":"123","marks":"0"},
{"userid":"21","name":"USER_21","subjectid":"123","marks":"0"},
{"userid":"22","name":"USER_22","subjectid":"123","marks":"0"},
{"userid":"23","name":"USER_23","subjectid":"123","marks":"0"},
{"userid":"24","name":"USER_24","subjectid":"123","marks":"0"},
{"userid":"25","name":"USER_25","subjectid":"123","marks":"0"},
{"userid":"26","name":"USER_26","subjectid":"123","marks":"0"},
{"userid":"27","name":"USER_27","subjectid":"123","marks":"0"},
{"userid":"28","name":"USER_28","subjectid":"123","marks":"0"},
{"userid":"29","name":"USER_29","subjectid":"123","marks":"0"},
{"userid":"30","name":"USER_30","subjectid":"123","marks":"0"},
{"userid":"31","name":"USER_31","subjectid":"123","marks":"0"},
{"userid":"32","name":"USER_32","subjectid":"123","marks":"0"},
{"userid":"33","name":"USER_33","subjectid":"123","marks":"0"}
];

console.log(JSON.stringify(arr));

arr.sort(function(a,b){
    return b['marks'] - a['marks'];
});

for(var i = 0; i < arr.length; i++){
        arr[i].position = i + 1;
}


console.log(JSON.stringify(arr));?

Answer 1

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