文件的输入输出
freopen("a.in", "r", stdin);//输出文件 a.in
freopen("a.out", "w", stdout);//输出文件 a.out
快读 & 快写
inline void read(int &x){
int 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();
x = s * w;
return ;
}
inline void write(int x) {
int num = 0;
char c[15];
while(x) c[++num] = (x%10)+48, x /= 10;
while(num) putchar(c[num--]);
putchar('
');
}