#include
using namespace std;
int main()
{
int a,b,c;
cin>>a>>b>>c;
if(0<=a<=100&&0<=b<=100&&0<=c<=100)
{
cout<<"score1="<<a<<",";
cout<<"score2="<<b<<",";
cout<<"score3="<<c;
}
else
cout<<"输入成绩错误";
}
当a=101时,0<=a<=100先判断0<=a为真,结果为1,然后1<100为真,所以0<=a<=100恒为1。
正确的写法是a>=0&&a<=100,要分开判断