View Compilation Error

0_0_31201775_29347.cpp: In function 'int main()':
0_0_31201775_29347.cpp:6:5: error: conflicting declaration 'int sum'
 int sum=0;
     ^
0_0_31201775_29347.cpp:4:29: note: previous declaration as 'unsigned int sum'
 unsigned int year,month,day,sum;
                             ^