1.加减乘除取余
（也是隐式转换）
int main(){
char ch = 'a';
char c = ch + 1;
char d = ch - 10;
printf("The character is %c\n",c);
printf("The character is %c\n",d);
return 0 ;
}
/*#include <stdio.h>
int main(){
char ch = 'If';
printf("The character is %c\n",ch);
printf("Its ascii value is %d\n",ch);
return 0 ;
}*/
/*#include <stdio.h>
int main(){
int a = 19;
int b = 9;
printf("%d\n",a + b);
printf("%d\n",a - b);
printf("%d\n",a * b);
printf("%f\n",a * 1.0 / b*1.0);
return 0;
}*/
/*#include <stdio.h>
int main(){
printf("输入一个数：\n");
int a,b;
int c = b ^10;
scanf("%d",&a);
printf("第%d位：%d\n",b+1,a / c % 10);
printf("百位：%d\n",a / 100 % 10);
printf("十位：%d\n",a / 10 % 10);
printf("个位：%d\n",a % 10);
return 0 ;
}
输出一个整数的各个位上的数字
#include <stdio.h>
int main(){
int a = 19;
short c = (short) a;
printf("%d\n",c);
}*///强制转换
