View Compilation Error

0_0_36679348_3187.cpp:20:1: error: '_int64' does not name a type
 _int64 ans;
 ^
0_0_36679348_3187.cpp: In function 'void merge(int, int, int)':
0_0_36679348_3187.cpp:24:48: error: 'ans' was not declared in this scope
   if(sum[h2]>sum[h1]) tmp[tmp_num++]=sum[h1++],ans+=r-h2+1;//h2h1h2
                                                ^
0_0_36679348_3187.cpp: In function 'int main()':
0_0_36679348_3187.cpp:49:1: error: 'ans' was not declared in this scope
 ans=0;//ans
 ^