STL HDOJ 5199 Gunner

题目传送门

 1 /*
 2     题意：问值为x的个数有几个，第二次查询就是0
 3     lower/upper_bound ()函数的使用，map也可过，hash方法不会
 4 */
 5 #include <cstdio>
 6 #include <cmath>
 7 #include <cstring>
 8 #include <algorithm>
 9 #include <iostream>
10 #include <vector>
11 #include <set>
12 #include <map>
13 #include <queue>
14 using namespace std;
15
16 const int MAXN = 1e6 + 10;
17 const int INF = 0x3f3f3f3f;
18 int a[MAXN], b[MAXN];
19 int used[MAXN];
20 int n, m;
21
22 inline int read(void)
23 {
24     int x = 0, f = 1;    char ch = getchar ();
25     while (ch < ‘0‘ || ch > ‘9‘)    {if (ch == ‘-‘) f = -1;    ch = getchar ();}
26     while (ch >= ‘0‘ && ch <= ‘9‘)    {x = x * 10 + ch - ‘0‘;    ch = getchar ();}
27     return f * x;
28 }
29
30 int main(void)        //HDOJ 5199 Gunner
31 {
32     //freopen ("B.in", "r", stdin);
33
34     while (scanf ("%d%d", &n, &m) == 2)
35     {
36         memset (used, 0, sizeof (used));
37         for (int i=1; i<=n; ++i)    a[i] = read ();
38         for (int i=1; i<=m; ++i)    b[i] = read ();
39
40         sort (a+1, a+1+n);
41         for (int i=1; i<=m; ++i)
42         {
43             int x = upper_bound (a+1, a+1+n, b[i]) - a;
44             int y = lower_bound (a+1, a+1+n, b[i]) - a;
45             if (used[x])
46             {
47                 puts ("0"); continue;
48             }
49             used[x] = 1;
50             printf ("%d\n", x - y);
51         }
52     }
53
54     return 0;
55 }

 1 #include <cstdio>
 2 #include <iostream>
 3 #include <cstring>
 4 #include <map>
 5 using namespace std;
 6
 7 const int MAXN = 1e6 + 10;
 8 const int INF = 0x3f3f3f3f;
 9
10 inline int read(void)
11 {
12     int x = 0, f = 1;    char ch = getchar ();
13     while (ch < ‘0‘ || ch > ‘9‘)    {if (ch == ‘-‘) f = -1;    ch = getchar ();}
14     while (ch >= ‘0‘ && ch <= ‘9‘)    {x = x * 10 + ch - ‘0‘;    ch = getchar ();}
15     return f * x;
16 }
17 int main(void)
18 {
19     //freopen ("B.in", "r", stdin);
20
21     int n, m;
22     while (scanf ("%d%d", &n, &m) == 2)
23     {
24         map<int, int> ma;    int x;
25         while (n--)
26         {
27             x = read ();   ma[x]++;
28         }
29         map<int, int>::iterator it;
30         while (m--)
31         {
32             x = read ();
33             it = ma.find (x);
34             if (it == ma.end ())
35                 puts ("0");
36             else
37             {
38                 printf ("%d\n", it->second);
39                 it->second = 0;
40             }
41         }
42     }
43
44     return 0;
45 }

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