HDU 1950 Bridging signals (DP動态規劃 + 二分搜尋 O(nlogn) )

#include <stdio.h>
#define MAX_POARTS 40000

int numOfTests;
int numOfPorts;
int arrayOfPorts[MAX_POARTS + 1];
//minTail[len]表示在所有長度為len的遞增子序列中的終止元素(也就是子序列中的最大值)裡面的最小值
int minTail[MAX_POARTS + 1];
//需要更新對應的minTail[lenOfIS]
int lenOfIS;//length of increasing subsequence
int result;//length of longest of increasing subsequence

//用二分搜尋的方法傳回minTail中port的下标,如果port不在minTail中，傳回第一個比port大的元素的下标
int binSearch(int port){
	int start = 1;
	int end = result;
	while (start <= end){
		int mid = (start + end) / 2;
		if (port < minTail[mid])
			end = mid - 1;
		else if(port > minTail[mid]) 
			start = mid + 1;
		else
			return mid；
	}
	return start;
}


int main(){

	scanf("%d", &numOfTests);
	int test;
	for (test = 1; test <= numOfTests; test++){
		scanf("%d", &numOfPorts);
		int indexOfPort;
		for (indexOfPort = 1; indexOfPort <= numOfPorts; indexOfPort++)
			scanf("%d", &arrayOfPorts[indexOfPort]);
			
		result = 1;
		minTail[result] = arrayOfPorts[1];
		for (indexOfPort = 2; indexOfPort <= numOfPorts; indexOfPort++){
			int port = arrayOfPorts[indexOfPort];
			lenOfIS = 0;
			if (port <= minTail[1])
				lenOfIS = 1;
			else if (port > minTail[result])
				lenOfIS = ++result;
			else if (port < minTail[result])
				lenOfIS = binSearch(port);
			minTail[lenOfIS] = port;
		}

		printf("%d\n", result);
	}

	return 0;
}