代码

#include<bits/stdc++.h>
using namespace std;
int a,b;
int ans,sum,s;
int main(){
	cin>>a>>b;
	for(int i=a;i<=b;i++){
		if(i%2==1){
			ans+=i;s++;
		}
		else if(i%2==0){
			sum+=i;s++;
		} 
	}
	for(int i=a;i<=b;i++){
		if(ans==sum){
			cout<<s;
		}
		else cout<<0;
	}
	return 0;
}

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