LeetCode第131场周赛(JAVA语言)

class Solution {
    public String removeOuterParentheses(String S) {
        Stack<String> s = new Stack<String>();
        String str  = "";
        for(int i=0;i<S.length();i++) {
        	if(S.charAt(i)=='('&&s.isEmpty()) {
        		s.add("(");
        	}else if(S.charAt(i)=='(') {
        		s.add("(");
        		str+="(";
        	}else if(S.charAt(i)==')'){
        		String s1 = s.pop();
        		if(!s.isEmpty()) {
        			str+=")";
        		}
        	}
        }
        return str;
    }
}

import java.math.BigInteger; 
class Solution {
	List<String> l1= new LinkedList<String>();
	String sum = "";
    public int sumRootToLeaf(TreeNode root) {
    	if(root==null) {
        	return 0;
        }
    		
    	dfs(root,sum,l1);   
    	 //1l 1-1-100101 =>2;
    	BigInteger count = BigInteger.ZERO;
    	for(int i=0;i<l1.size();i++) {
    		BigInteger b = new BigInteger(l1.get(i), 2);
    		count = count.add(b);
    	}
    	BigInteger j = new BigInteger("1000000007");
    	count = count.mod(j);
    	return count.intValue();
    }
	private void dfs(TreeNode root, String sum, List<String> l1) {
		// TODO Auto-generated method stub
		 sum += root.val;   
        if(root.right==null&&root.left==null) {
        	l1.add(sum);  	
        }
        if(root.left!=null) {
        	dfs(root.left,sum,l1);
        }
        if(root.right!=null) {
        	dfs(root.right,sum,l1);
        }
        
	}
	
}

class Solution {
    public List<Boolean> camelMatch(String[] queries, String pattern) {
        char[] pt = pattern.toCharArray();
        int m = pt.length;
        List<Boolean> ret = new ArrayList<>();
        outer:
        for(String q : queries){
        	int p = 0;
        	for(char c : q.toCharArray()){
        		if(p < m && pt[p] == c){
        			p++;
        		}else{
        			if(!('a' <= c && c <= 'z')){
        				ret.add(false);
        				continue outer;
        			}
        		}
        	}
        	ret.add(p == m);
        }
        return ret;
    }
}	

class sp{
	int x,y;
}
class Solution {
	LinkedList<sp> l1= new LinkedList<>();
	
    public int videoStitching(int[][] clips, int T) {
    	for(int i=0;i<clips.length;i++) {
    		sp s = new sp();
    		s.x = clips[i][0];
    		s.y = clips[i][1];
     		l1.add(s);
    	}
    	l1.sort(new Comparator<sp>() {
			@Override
			public int compare(sp o1, sp o2) {
				// TODO Auto-generated method stub
				if(o1.x==o2.x) {
					return o2.y - o1.y;
				}
				return o1.x - o2.x;
			}		
		});
    	/*for(int i=0;i<l1.size();i++) {
    		System.out.println(l1.get(i).x + " " +l1.get(i).y);
    	}*/
    
    	if(l1.get(0).x!=0) {
    		return -1;
    	}
    	int n = clips.length;
    	int now=0,ans=0,i=0;
    	while(now<T&&i<clips.length) {
    		int max = now;
    		while(i<n&&l1.get(i).x<=now) {
    			max = Math.max(max, l1.get(i).y);
    			i++;
    		}
    		if(max == now) {
    			break;
    		}
    		now = max;
    		ans++;
    	}
    	if(now<T) {
    		return -1;
    	}
    	return ans;
    }
}

结束