inline long long mx() {
long long s = 0,w = 1;
char ch = getchar();
while(ch < ‘0‘ || ch > ‘9‘) {
if(ch == ‘-‘) w = -1;
ch = getchar();
}
while(ch >= ‘0‘ && ch <= ‘9‘) {
s = s * 10 + (ch - ‘0‘);
ch = getchar();
}
return s * w;
}原文：https://www.cnblogs.com/lipeiyi520/p/13933992.html