View Compilation Error

0_0_26083049_10991.cpp: In function 'int main()':
0_0_26083049_10991.cpp:2:56: error: expected ';' before string constant
 int main(){long long n;while(scanf("%d",&n)!=EOF)printf"%I64d\n\n",(n+1)*n/2);}
                                                        ^