View Compilation Error

0_0_15986816_10419.cpp: In function 'int main()':
0_0_15986816_10419.cpp:6:12: error: 'n' was not declared in this scope
 for(i=1;i<=n;i++)
            ^
0_0_15986816_10419.cpp:9:12: error: 'm' was not declared in this scope
 for(j=1;j<=m;j++)
            ^