题目:
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题解:
cpp
class Solution {
public:
string convertToBase7(int num) {
if (num == 0) {
return "0";
}
bool negative = num < 0;
num = abs(num);
string digits;
while (num > 0) {
digits.push_back(num % 7 + '0');
num /= 7;
}
if (negative) {
digits.push_back('-');
}
reverse(digits.begin(), digits.end());
return digits;
}
};