View Compilation Error

0_0_31096247_20665.cpp:5:1: error: stray '\243' in program
 scanf("%d",&n)；
 ^
0_0_31096247_20665.cpp:5:1: error: stray '\273' in program
0_0_31096247_20665.cpp:2:11: error: '::main' must return 'int'
 void main()
           ^
0_0_31096247_20665.cpp: In function 'int main()':
0_0_31096247_20665.cpp:6:1: error: expected ';' before 'printf'
 printf("%d\n",n*(n+1)/2);
 ^
0_0_31096247_20665.cpp:7:1: error: 'retuan' was not declared in this scope
 retuan 0;
 ^