string to sum
JavaScript
var str = "(1,50),(3,50),(5,50)",
sum = 1;
var strA = str.split('(').join('').split('),');
strA[strA.length - 1] = strA[strA.length - 1].replace(')', '');
for (i = 0; i < strA.length; i++) {
var set = strA[i].split(',');
if (!isNaN(set[1])) {
sum = sum * set[1];
}
}
console.log(sum);