题解 | #第一个只出现一次的字符#
第一个只出现一次的字符
https://www.nowcoder.com/practice/1c82e8cf713b4bbeb2a5b31cf5b0417c?tpId=265&rp=1&ru=%2Fexam%2Foj%2Fta&qru=%2Fexam%2Foj%2Fta&sourceUrl=%2Fexam%2Foj%2Fta%3FjudgeStatus%3D3%26page%3D1%26pageSize%3D50%26search%3D%26tpId%3D13%26type%3D265&difficulty=&judgeStatus=3&tags=&title=&gioEnter=menu
class Solution {
public:
int FirstNotRepeatingChar(string str) {
if (str.empty()) {
return -1;
}
int res = -1;
std::unordered_map<char, int> count;
for (int i = 0; i < str.size(); ++i) {
++count[str[i]];
}
for (int i = 0; i < str.size(); ++i) {
if (count[str[i]] == 1) {
res = i;
break;
}
}
return res;
}
};
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