#include <stdio.h>
int main(void) {
int a,b,c;
scanf("%d%d%d",&a
,&b
,&c
); printf("平均成绩是:%.2f\n",a
+b
+c
/3.0); return 0;
}
I2luY2x1ZGUgPHN0ZGlvLmg+CgppbnQgbWFpbih2b2lkKSB7CglpbnQgYSxiLGM7CiAgICBwcmludGYoIuivt+i+k+WFpeS4ieS4quS6uueahOaIkOe7qSIpOwogICAgc2NhbmYoIiVkJWQlZCIsJmEsJmIsJmMpOwogICAgcHJpbnRmKCLlubPlnYfmiJDnu6nmmK86JS4yZlxuIixhK2IrYy8zLjApOwoJcmV0dXJuIDA7Cn0K