#include<bits/stdc++.h> using namespace std; int abc(int n,int m){//形参 int sum=0; for(int i=n;i<=m;i++) sum+=i; return sum; } int main(){ cout<<abc(1,10)<<endl;//实参 cout<<abc(20,30)<<endl; cout<<abc(35,45)<<endl; return 0; }