function Student(id, name, sClass) {
    this.id = id;
    this.name = name;
    this.class = sClass;
    this.priorities = [];
    this.history = {};
}

function indexOf(priorities, student) {
    if (priorities == null || priorities.length == 0) return -1;
    for (m = 0; m < priorities.length; m++) {
        var current = priorities[m];
        if (current == student.id) return m;
    }
    return -1;
}

Student.prototype.addToHistory = function(other) {
    var id = other.id;
    var value = this.history[id];
    if (value == null) this.history[id] = 1;
    else this.history[id] = this.history[id] + 1;
}

// How many times has this student been in a group with another student compared to how many groups that has been formed in total
Student.prototype.getFrequency = function(other) {
    var occurences = this.history[other.id];
    if (occurences == null) return 0;
    return groupCount / occurences;
}

// Calculate a value symbolizing how good these two students are matched
Student.prototype.getRelationValue = function(other) {
    var index1 = indexOf(this.priorities, other);
    var index2 = indexOf(other.priorities, this);
    if (index1 == -1) index1 = defaultIndex;
    if (index2 == -1) index2 = defaultIndex;
    index1++;
    index2++;
    var frequency = this.getFrequency(other);
    return (index1 + index2) * frequency;
}
Setting Validate Copy Format