0_0_29307297_15536.cpp: In function 'int main()': 0_0_29307297_15536.cpp:17:7: error: 'i' was not declared in this scope for(i=0;i<n;i++) ^ 0_0_29307297_15536.cpp:19:13: error: 'arr' was not declared in this scope arr[i][i]=0; ^