http://acm.hdu.edu.cn/showproblem.php?pid=1025
很难说清楚,自己模拟几下就会慢慢明白,模板题
求的是最长递增子序列的长度
#include <iostream>
#include <fstream>
#include <algorithm>
#include <string>
#include <set>
//#include <map>
#include <queue>
#include <utility>
#include <iomanip>
#include <stack>
#include <list>
#include <vector>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <cmath>
//#include <ctime>
#include <ctype.h>
using namespace std;
#define LL __int64
#define inf 0x3fffffff
#define M 500005
int v[M];
int main()
{
int n, i, tv, x, cc = 1, top;
while (~scanf ("%d", &n))
{
memset (v, 0, sizeof(v));
for (i = 0; i < n; i++)
{
scanf ("%d%d", &x, &tv);
v[x-1] = tv;
}
/********************模板********************/
top = 0;
for (i = 0; i < n; i++)
{
int *p = lower_bound (v, v+top, v[i]);
if (p - v == top)
++top;
*p = v[i];
}
/********************模板********************/
printf ("Case %d:\n", cc++);
if (top <= 1)
printf ("My king, at most %d road can be built.\n\n", top);
else
printf ("My king, at most %d roads can be built.\n\n", top);
}
return 0;
}