# cpp problem Why `bool B` becomes 0? ```cpp= #include<iostream> using namespace std; int main () { bool B = false; cout << B << endl; if (1) { cout << B << endl; if (1) { cout << B << endl; if (1) { cout << B << endl; bool B = true; cout << B << endl; } cout << B << endl; } cout << B << endl; } cout << B << endl; cout << "#################" << endl; bool L = false; cout << L << endl; if (1) { cout << L << endl; if (1) { cout << L << endl; if (1) { cout << L << endl; L = true; cout << L << endl; } cout << L << endl; } cout << L << endl; } cout << L << endl; return 1; } ``` ## result ```typescript= 0 0 0 0 1 0 0 0 ################# 0 0 0 0 1 1 1 1 ```