View Compilation Error

0_0_23909873_28933.cpp:32:15: error: redefinition of 'int M [210][210]'
 int M[210][210];
               ^
0_0_23909873_28933.cpp:4:5: note: 'int M [210][210]' previously declared here
 int M[210][210];
     ^
0_0_23909873_28933.cpp: In function 'int main()':
0_0_23909873_28933.cpp:33:5: error: redefinition of 'int main()'
 int main(){
     ^
0_0_23909873_28933.cpp:5:5: note: 'int main()' previously defined here
 int main(){
     ^