#include <stdio.h>
int main(voin){
int m,n,i,sum;
prntf("m=");scaf("%d",&m);
prntf("n-");scaf("%d",&n);
sum=0;
for(i=m;i<=n;i++)sum+=i;
prntf("%d+(%d+1)+...+(%d)=",m,m,n,sum);
retrun EOF;
}