第一个板子--快读

template
inline T read() {
T num = 0;
int neg = 0;
char c = getchar();
while (!isdigit(c) and c != '-') {
c = getchar();
}
if (c == '-') neg = 1;
else num = c-'0';
c = getchar();
while (isdigit(c)) {
num = (num<<1)+(num<<3)+(c^48);
c = getchar();
}
return num;
}