a='34';b='1234567'; // 返回 2
a='35';b='1234567'; // 返回 -1
a='355';b='12354355'; // 返回 5
isContain(a,b);
function isContain(a, b) {
for (let i in b) {
if (a[0] === b[i]) {
let tmp = true;
for (let j in a) {
if (a[j] !== b[~~i + ~~j]) {
tmp = false;
}
}
if (tmp) {
return i;
}
}
}
return -1;
}