Main.cc: In function 'int main()': Main.cc:9:17: error: array must be initialized with a brace-enclosed initializer int a[21][21]=(0); ^ Main.cc:20:32: error: expected ';' before ')' token for(int j=n-i-2&&t<=n*n;j--){ ^ Main.cc:24:21: error: expected primary-expression before ';' token a[j][i]=j+ +; ^