Longest Common Prefix

var longestCommonPrefix = function(strs) {
if (strs.length < 1) {
return "";
}

var prefix = strs[0];

for (var i = 1; i < strs.length; i++) {
if (prefix.length < 1) {
return "";
}

var len = prefix.length < strs[i].length ? prefix.length : strs[i].length;

for (var j = 0; j < len; j++) {
if (prefix[j] != strs[i][j]) {
break;
}
}

prefix = prefix.substr(0, j);
}

return prefix;
};