#include<stdio.h> int main() { long long i,n,sum; scanf("%lld",&n); for(i=1,sum=0;i<=n;i++) sum=sum+i; printf("%lld\n",sum); }
By signing up a 追梦算法网 universal account, you can submit code and join discussions in all online judging services provided by us.
Using your 追梦算法网 universal account
