类型转换：数字转为字符，字符转为数字

#include <stdio.h> 
int main()
{ 
   int number = 86; 
   char letter = 'M'; 
   printf("\n86 type-casted to char is: %c\n", (char) number); 
   printf("\n'M' type-casted to int is: %d\n ", (int) letter); 
}