void read(int &x){
char c=getchar();
int t=1;
x=0;
while(c<'0' || c>'9'){
if(c=='-') t=-t;
c=getchar();
}
while(c>='0' && c<='9'){
x=(x<<1)+(x<<3)+(c-'0');
c=getchar();
}
x*=t;
}
void write(int x){
if(x<0){
putchar('-');
x=-x;
}
if(x>=10){
write(x/10);
}
putchar(x%10+'0');
}
压行:
void read(int &x){char c=getchar();int t=1;x=0;while(c<'0' || c>'9'){if(c=='-'){t=-t;}c=getchar();}while(c>='0' && c<='9'){x=(x<<1)+(x<<3)+(c-'0');c=getchar();}x*=t;}
void write(int x){if(x<0){putchar('-');x=-x;}if(x>=10){write(x/10);}putchar(x%10+'0');}