Help me to understand this part of ccode, i dont understand how it works , since while to if

[wary badge]

var longestCommonPrefix = function(strs) {
if (strs.length === 0) return "";
let prefix = strs[0];
for (let i = 1; i < strs.length; i++) {
while (strs[i].indexOf(prefix) !== 0) {
prefix = prefix.slice(0, -1);
if (!prefix) return "";
}
}
return prefix;
};

while (strs[i].indexOf(prefix) !== 0) {
prefix = prefix.slice(0, -1);
if (!prefix) return "";
this part

i dont understnad hpw indexOf works

[lone relic]

it finds where prefix exists inside strs[i], or -1 if it isn't present

though !strs[i].startsWith(prefix) would make more sense

https://justlink.to/mdn/string.indexof

see docs ^