简单地遍历一遍就可了
class Solution {
public:
int countSeniors(vector<string>& details) {
int n=details.size();
int res=0;
for(int i=0;i<n;i++){
int sum=(details[i][11]-'0')*10+(details[i][12]-'0');
if(sum>60){
res++;
}
}
return res;
}
};