View Compilation Error

0_0_22776614_1051.cpp:29:11: error: redefinition of 'const int maxn'
 const int maxn = 505;
           ^
0_0_22776614_1051.cpp:6:11: note: 'const int maxn' previously defined here
 const int maxn = 505;
           ^
0_0_22776614_1051.cpp:30:11: error: redefinition of 'int a [505]'
 int a[maxn];
           ^
0_0_22776614_1051.cpp:7:5: note: 'int a [505]' previously declared here
 int a[maxn];
     ^
0_0_22776614_1051.cpp: In function 'int main()':
0_0_22776614_1051.cpp:31:5: error: redefinition of 'int main()'
 int main()
     ^
0_0_22776614_1051.cpp:8:5: note: 'int main()' previously defined here
 int main()
     ^