Add Binary
Given two binary strings a and b, return their sum as a binary string.
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| Example 1:
Input: a = "11", b = "1"
Output: "100"
Example 2:
Input: a = "1010", b = "1011"
Output: "10101"
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C++ Solution
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| string addBinary(string a, string b) {
int carry = 0;
auto a_iter = a.rbegin();
auto b_iter = b.rbegin();
stack<char> myStack;
while (a_iter != a.rend() || b_iter != b.rend() || carry != 0) {
int val = 0;
if (a_iter != a.rend() && b_iter != b.rend()) {
val = (*a_iter - '0') + (*b_iter - '0') + carry;
} else if (a_iter != a.rend() && b_iter == b.rend()) {
val = (*a_iter - '0') + carry;
} else if (a_iter == a.rend() && b_iter != b.rend()) {
val = (*b_iter - '0') + carry;
} else {
val = carry;
}
carry = val / 2;
myStack.push(val % 2 + '0');
if (a_iter != a.rend()) {
a_iter++;
}
if (b_iter != b.rend()) {
b_iter++;
}
}
string ret;
while (!myStack.empty()) {
ret.push_back(myStack.top());
myStack.pop();
}
return ret;
}
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