Heap implementation using TypeScript

min-heap.ts

class MinHeap {
    readonly nodes: number[];
    
    constructor(private size: number) {
        this.nodes = [null];
    }
    
    getMin(): number { 
        return this.nodes[1];
    }

    insert(val: number) {
        this.nodes.push(val);
        this.sort();
    }

    pop(): number {
        if (this.nodes.length === 0) { 
            return void 0;
        }
        if (this.nodes.length === 1) {
            return this.nodes.pop();
        }
        
        // swap the first node and the last node
        ;[this.nodes[0], this.nodes[this.nodes.length - 1]] = [this.nodes[this.nodes.length - 1], this.nodes[0]];
        
        const last = this.nodes.pop();
        this.sort();
        
        return last;
    }
    
    private sort() {
        if (this.nodes.length > 2) { 
            let ptr = this.nodes.length - 1;
            
            while(ptr >= 1) { 
                let parent = Math.floor(ptr/2);
                if (ptr !== parent && this.nodes[ptr] < this.nodes[parent]) {
                    [this.nodes[ptr], this.nodes[parent]] = [this.nodes[parent], this.nodes[ptr]];
                }
                --ptr;
            }
        }
    }
}