View Compilation Error

0_0_24927195_15763.cpp:1:1: error: 'n' does not name a type
 n;main(){for(;~scanf("%d",&n);printf("%d\n",n*(n+1)/2));}
 ^
0_0_24927195_15763.cpp: In function 'int main()':
0_0_24927195_15763.cpp:1:28: error: 'n' was not declared in this scope
 n;main(){for(;~scanf("%d",&n);printf("%d\n",n*(n+1)/2));}
                            ^
0_0_24927195_15763.cpp:1:29: error: 'scanf' was not declared in this scope
 n;main(){for(;~scanf("%d",&n);printf("%d\n",n*(n+1)/2));}
                             ^
0_0_24927195_15763.cpp:1:54: error: 'printf' was not declared in this scope
 n;main(){for(;~scanf("%d",&n);printf("%d\n",n*(n+1)/2));}
                                                      ^