3月5号奇安信笔试编程题
第一题，最长上升子序列
public static int LSubSequence (int N, ArrayList<Integer> sequence) {
// write code here
int[] dp = new int[N];
Arrays.fill(dp,1);
int max=1;
for (int i = 0; i < sequence.size(); i++) {
for (int j = 0; j < i; j++) {
if (sequence.get(j)<sequence.get(i)){
dp[i]=Math.max(dp[j]+1,dp[i]);
max=Math.max(dp[i],max);
}
}
}
return max;
} 第二题，满足正确括号闭合的字符串个数 public static int count (ArrayList<String> arr) {
// write code here
int count=0;
for (int i = 0; i < arr.size(); i++) {
if(test(arr.get(i))){
count++;
}
}
return count;
}
public static boolean test(String s){
if (!s.contains("(")&&!s.contains("(")){
return false;
}
Stack<Character> stack = new Stack<Character>();
for (int i = 0; i < s.length(); i++) {
if (s.charAt(i)=='('){
stack.push(')');
}else if (stack.isEmpty()||stack.pop()!=s.charAt(i)){
return false;
}
}
return stack.isEmpty();
} 
