#include<iostream> // cin\cout\endl #include<cstdio> //scanf()\printf() #include<cstring> // strcpy()\strcat()\strcmp()\strlen()\memset() #include<cmath> //sqrt()\pow()\abs()\ceil()\floor()\max()\min() using namespace std; int sum(int x,int y){ int s=0; for(int i=x;i<=y;i++){ s+=i; } cout<<s<<endl; return s; } int main(){ sum(1,10); sum(20,30); sum(35,45); return 0; }