Given a string containing just the characters '(', ')',
'{', '}', '[' and ']', determine if the input string is valid.
The brackets must close in the correct order, "()" and "()[]{}" are all valid but
"(]" and "([)]" are not.
class Solution {
public:
bool isValid(string s) {
stack<char, vector<char> > lifo;
lifo.push('#');
for (size_t i=0; i<s.size(); i++) {
if (s[i] == '{' ||
s[i] == '[' ||
......
阅读全文