int a=100; float b=20.54446; double c=63.1234; char q=’m’;
    printf(“%d\n”,a);
    printf(“%f\n”,b);
    printf(“%lf\n”,c); //可是lf或f
    printf(“%c\n”,q);

    printf(“%4d\n”,a); //未满四位，以空格填充
    printf(“%04d\n”,a); //未满四位，以零填充
    printf(“%2d\n”,a); //限制位数小于实际位数，则显示实际位数
    printf(“%-9dint\n”,a); //左对齐
    printf(“%9dint\n”,a);
    printf(“%10.4f\n”,b); //限制宽度为十
    printf(“%010.4f\n”,b); //宽度为十，后四位四舍五入，以零填充
    |——————————
    |100
    |20.544460
    |63.123400
    |m
    | 100
    |0100
    |100
    |100 int
    | 100int
    | 20.5445
    |00020.5445
    |