#include using namespace std; int main(){ double m,h; cin>>m>>h; double BMI=1.0m/(hh); if(BMI<18.5){ cout<<"Underweight"<<endl; }else if(BMI>=18.5&&BMI<24){ cout<<"Normal"<<endl; }else if(BMI>=24){ cout<<BMI<<endl; cout<<"Overweight"<<endl; } return 0; }

#include using namespace std; int main(){ double m,h; cin>>m>>h; double BMI=1.0m/(hh); if(BMI<18.5){ cout<<"Underweight"<<endl; }else if(BMI>=18.5&&BMI<24){ cout<<"Normal"<<endl; }else if(BMI>=24){ cout<<BMI<<endl; cout<<"Overweight"<<endl; } return 0; }

using namespace std;
int main()
{
	double a,b;
	cin>>a>>b;
	a=a/(b*b);
	if(a<18.5)
	{
		cout<<"Underweight";
	}
	else if(a>=18.5&&a<24)
	{
		cout<<"Normal";
	}
	else
	{
		cout<<a;
		cout<<endl;
		cout<<"Overweight";
	}
	
	return 0;
}

判断就好了，但要用double

#include <iostream>
using namespace std;
int main(){
    double m,h;
    cin>>m>>h;
    double BMI=1.0*m/(h*h);
    if(BMI<18.5){
        cout<<"Underweight"<<endl;
    }else if(BMI>=18.5&&BMI<24){
        cout<<"Normal"<<endl;
    }else if(BMI>=24){
        cout<<BMI<<endl;
        cout<<"Overweight"<<endl;
    }
    return 0;
}

注意，身高不是整数，BMI也不是整数。 剩下的，正常计算就可以了，再来三个比较，就OK了！！！ 如有错请指出。

代码：

#include<bits/stdc++.h>
typedef double ll;
using namespace std;
const int N=10010;
ll h;
ll m; 
int main(){

	cin.sync_with_stdio(false);
	ios::sync_with_stdio(0);
	cin>>m>>h;
	ll BMI=m/(h*h);
	if(BMI<18.5){
		cout<<"Underweight";
	} 
	else if(BMI>=18.5&&BMI<24){
		cout<<"Normal"; 
	}
	else{
		cout<<BMI<<'\n'; 
		cout<<"Overweight";
	}


	return 0;
}

#include <bits/stdc++.h>
#include <cmath>
using  namespace std;
int main() {
    double a,b,c;
    cin>>a>>b;
    c=a/(b*b);
    if(c<18.5){
        cout<<"Underweight";
    }
    else if(c>=18.5&&c<24){
        cout<<"Normal";
    }
    else if(c>=24){
        cout<<c<<endl<<"Overweight";
    }
	
	return 0;
}