View Compilation Error

0_0_16524364_432.cpp: In function 'int main()':
0_0_16524364_432.cpp:4:5: error: '_int64' was not declared in this scope
     _int64 sum,i,n;
     ^
0_0_16524364_432.cpp:5:26: error: 'n' was not declared in this scope
     while(scanf("%I64d",&n)!=EOF)
                          ^
0_0_16524364_432.cpp:7:9: error: 'sum' was not declared in this scope
         sum=1;
         ^
0_0_16524364_432.cpp:8:13: error: 'i' was not declared in this scope
         for(i=1;i<=n;i++)
             ^