从键盘输入一个整数:
int num;scanf("%d", &num);从键盘输入两个整数:int num1, num2;scanf("%d %d", &num1, &num2);从键盘输入一个浮点数:float num;scanf("%f", &num);从键盘输入一个字符串:char str[50];scanf("%s", str);从键盘输入一个字符:char ch;scanf(" %c", &ch);从键盘输入多个数据,以空格或换行符分隔:int num1, num2;char ch;scanf("%d %d %c", &num1, &num2, &ch); 

