Question

I’m new to JS function and objects
I’m trying to iterate an array…this is my sample code which i was trying to get the multiples of coins with an input value

var flag=0;var chipval=0;var num=0;
var main = function(coins){
        var coinsarr = [1,5,10,25,50,100,500,501];var length=coinsarr.length
        var remval = coins;
        var coinskey = "";
        while(flag==0){
            for(i=0;i<length;i++){
                if(coinsarr[i]>remval){
                    chipval = coinsarr[i-1];
                    num = parseInt(remval/chipval);
                    if(remval%chipval==0){
                        flag = 1;
                        break;
                    }else{
                        remval=remval%chipval;
                        $flag = 0;
                        break;
                    }
                }
            }
            coinskey = coinskey+","+chipval+":"+num;
        }
        coinskey = coinskey.replace(/(^,)|(,$)/g, "")
        alert(coinskey);
    }

when i run main(120), this will return 100:2,10:2(which is nothing by 100coins of 2 and 10coins of 2)

When i run main(720), i’m getting memory leaks…which says “Script on this page used too much memory”;
Can anyone tell me, where the issue is or else is this the right way to proceed ??

Thanks for your time and patience…

Answer 1

A slightly cleaner option to get a amount of coins to make up a value, would be to build a object containing the values. Something like this will do the trick:

function coins(value){
    var coinsarr = [1,5,10,25,50,100,500,501];
    var out = {};
    while(value > 0){
        var i = 0;
        while(coinsarr[i+1] <= value){
            i++; // Find the coin to add.
        }
        var coin = coinsarr[i];
        value -= coin;
        if(!out[coin]){
            out[coin] = 0;
        }
        out[coin]++;
    }
    return out;
}

coins(499);
// {        Returns:
//     1: 4
//     10: 2
//     25: 1
//     50: 1
//     100: 4
// }
coins(21359);
// {        Returns:
//     1: 2
//     5: 1
//     10: 1
//     100: 3
//     501: 42
// }

The advantage of this is that you can retrieve the values easier than having to parse a string:

var coinsObj = coins(499);
for(var key in coinsObj){
    console.log(coinsObj[key] + ' times coin "' + key + '"' );
}
// 4 times coin "1"
// 2 times coin "10"
// 1 times coin "25"
// 1 times coin "50"
// 4 times coin "100"

Or just build a string like this:

var coinsObj = coins(499);
var outString = ''
for(var key in coinsObj){
    outString += ',' + key + ':' + coinsObj[key];
}
outString = outString.substr(1); // Remove the leading comma.