快读及快写

`read()`

inline int read(){
    int x = 0;
    int f = 1; 
    char ch = getchar();
 
    while(ch < '0' || ch > '9'){
        if(ch == '-') f = -1;
        ch = getchar();
    }
 
    while(ch >= '0' && ch <= '9'){
        x = x * 10 + (ch - '0');
        ch = getchar();
    }
 
    return x * f;
}

`write()`

inline void write(int x){
    if(x < 0){
        cout << '-';
        x = - x;
    }
 
    if(x > 9){
        write(x / 10);
    }
 
    putchar((char)(x % 10 + '0'));
}