draw a 4*4 matrix in typescript and exchange two column values based on row index

working link
https://stackblitz.com/edit/typescript-omoaq4

code =>

//draw a matrix and exchange two column values in the matrix based on given row index

class matrix

{

static rm=[];

static rc=[];

static drawMatrix(r:number,c:number)

{

//n2

var k=0;

for(let i=0,k=0;i<r;i++)

{

this.rc=[];

for(let j=0;j<c;j++,k++)

{

this.rc.push(String.fromCharCode(64+(k+1)));

}

this.rm.push(this.rc);

}

}

static exchangeRowData(rowIndex,col1,col2)

{

let currentRow=this.rm[rowIndex];

let temp=currentRow[this.getIndex(currentRow,col1)];

let index=this.getIndex(currentRow,col2);

currentRow[this.getIndex(currentRow,col1)]=currentRow[index];

currentRow[index]=temp;

}

static getIndex(arry,value)

{

for(var i=0;i<arry.length;i++)

{

if(arry[i]===value)

{

return i;

}

}

}

static getMatrix()

{

return this.rm;

}

}

matrix.drawMatrix(4,4);

console.log(matrix.getMatrix());

matrix.exchangeRowData(1,"E","F");

console.log(matrix.getMatrix());