1:  int main()

   2:  {

   3:      /*

   4:      int score;

   5:      // 赋值操作（初始化）

   6:      score = 1000;

   7:      

   8:      score = 10000;

   9:      

  10:      char c;

  11:      

  12:      c = ‘A‘;

  13:      

  14:      int a = 20;

  15:      

  16:      

  17:      //int d,e,f;

  18:      

  19:      int b;

  20:      

  21:      b = a = 40;

  22:      

  23:      b = 30;*/

  24:      

  25:      // 变量：只要有不确定的数据， 就应该定义变量来保存

  26:      int score = 205;

  27:      // 1:15

  28:      int time = 75;

  29:      

  30:      int bestScore = 3161;

  31:      

  32:      // %d\%i是一个格式符（占位符），只能输出整数

  33:      printf("分数是%d\n", score);

  34:      

  35:      

  36:      float height = 1.78f;

  37:      

  38:      // %f用来输出小数，默认是6位小数

  39:      printf("身高是%.2f\n", height);

  40:      

  41:      

  42:      char scoreGrade = ‘D‘;

  43:      printf("积分等级是%c\n", scoreGrade);

  44:      

  45:      

  46:      printf("分数是%d，身高是%f，等级是%c\n", score, height, ‘C‘);

  47:      

  48:      return 0;

  49:  }

   1:  int temp = a;

   2:  a = b;

   3:  b = temp; 

   1:  a = b - a;

   2:  b = b - a;

   3:  a = b + a;