# Set of real numbers

## Solutions

Solution 1 (Click to Show/Hide)
``````function realSet(set1, set2, operation, values) {
const RangeType = {
CLOSED: 0,
BOTH_OPEN: 1,
LEFT_OPEN: 2,
RIGHT_OPEN: 3
};

function Predicate(test) {
this.test = test;
this.or = function(other) {
return new Predicate(t => this.test(t) || other.test(t));
};
this.and = function(other) {
return new Predicate(t => this.test(t) && other.test(t));
};
this.negate = function() {
return new Predicate(t => !this.test(t));
};
}

function RealSet(start, end, rangeType, predF) {
this.low = start;
this.high = end;

if (predF) {
this.predicate = new Predicate(predF);
} else {
this.predicate = new Predicate(d => {
switch (rangeType) {
case RangeType.CLOSED:
return start <= d && d <= end;
case RangeType.BOTH_OPEN:
return start < d && d < end;
case RangeType.LEFT_OPEN:
return start < d && d <= end;
case RangeType.RIGHT_OPEN:
return start <= d && d < end;
}
});
}

this.contains = function(d) {
return this.predicate.test(d);
};

this.union = function(other) {
var low2 = Math.min(this.low, other.low);
var high2 = Math.max(this.high, other.high);
return new RealSet(low2, high2, null, d =>
this.predicate.or(other.predicate).test(d)
);
};

this.intersect = function(other) {
var low2 = Math.min(this.low, other.low);
var high2 = Math.max(this.high, other.high);
return new RealSet(low2, high2, null, d =>
this.predicate.and(other.predicate).test(d)
);
};

this.subtract = function(other) {
return new RealSet(this.low, this.high, null, d =>
this.predicate.and(other.predicate.negate()).test(d)
);
};
}
set1 = new RealSet(set1.low, set1.high, set1.rangeType);
set2 = new RealSet(set2.low, set2.high, set2.rangeType);
var result = [];
values.forEach(function(value) {
result.push(set1[operation](set2).contains(value));
});
return result;
}
``````