View Compilation Error

0_0_16124074_22530.cpp:7:1: error: '_int64' does not name a type
 _int64 gunpower[1000005];
 ^
0_0_16124074_22530.cpp: In function 'int main()':
0_0_16124074_22530.cpp:21:25: error: 'gunpower' was not declared in this scope
             scanf("%d",&gunpower[i]);
                         ^
0_0_16124074_22530.cpp:24:14: error: 'gunpower' was not declared in this scope
         sort(gunpower,gunpower+n,cmp);
              ^