最关键的是要重右上角开始比较!
class Solution {
public:
bool Find(int target, vector<vector<int> > array) {
int a = 0;
int b = array.size()-1;
while(b>=0&&a<array[0].size()){
if(target==array[a][b]) return true;
else if(target<array[a][b]) b--;
else a++;
}
return false;
}
};