HDU 1556 - Color the ball (树状数组 | 线段树)
思路
都忘了树状数组长什么样了。。模板题，趁机回忆了一下。
代码（树状数组）
#include <cstdio>
#include <stack>
#include <set>
#include <iostream>
#include <string>
#include <vector>
#include <queue>
#include <functional>
#include <cstring>
#include <algorithm>
#include <cctype>
#include <ctime>
#include <cstdlib>
#include <fstream>
#include <string>
#include <sstream>
#include <map>
#include <cmath>
#define LL long long
#define SZ(x) (int)x.size()
#define Lowbit(x) ((x) & (-x))
#define MP(a, b) make_pair(a, b)
#define MS(arr, num) memset(arr, num, sizeof(arr))
#define PB push_back
#define F first
#define S second
#define ROP freopen("input.txt", "r", stdin);
#define MID(a, b) (a + ((b - a) >> 1))
#define LC rt << 1, l, mid
#define RC rt << 1|1, mid + 1, r
#define LRT rt << 1
#define RRT rt << 1|1
#define BitCount(x) __builtin_popcount(x)
const double PI = acos(-1.0);
const int INF = 0x3f3f3f3f;
using namespace std;
const LL MAXN = 1e5 + 10;
const int MOD = 20071027;
typedef pair<int, int> pii;
typedef vector<int>::iterator viti;
typedef vector<pii>::iterator vitii;
int C[MAXN], n;
int GetValue(int x)
{
int sum = 0;
while (x > 0)
{
sum += C[x];
x -= Lowbit(x);
}
return sum;
}
void Update(int x, int v)
{
while (x <= n)
{
C[x] += v;
x += Lowbit(x);
}
}
int main()
{
//ROP;
int i, j;
while (scanf("%d", &n), n)
{
fill(C, C + n + 1, 0);
int a, b;
for (i = 0; i < n; i++)
{
scanf("%d%d", &a, &b);
Update(a, 1);
Update(b + 1, -1);
}
for (i = 1; i <= n; i++)
{
if (i == n) printf("%d\n", GetValue(i));
else printf("%d ", GetValue(i));
}
}
return 0;
}
线段树
#include <cstdio>
#include <stack>
#include <set>
#include <iostream>
#include <string>
#include <vector>
#include <queue>
#include <functional>
#include <cstring>
#include <algorithm>
#include <cctype>
#include <ctime>
#include <cstdlib>
#include <fstream>
#include <string>
#include <sstream>
#include <map>
#include <cmath>
#define LL long long
#define SZ(x) (int)x.size()
#define Lowbit(x) ((x) & (-x))
#define MP(a, b) make_pair(a, b)
#define MS(arr, num) memset(arr, num, sizeof(arr))
#define PB push_back
#define F first
#define S second
#define ROP freopen("input.txt", "r", stdin);
#define MID(a, b) (a + ((b - a) >> 1))
#define LC rt << 1, l, mid
#define RC rt << 1|1, mid + 1, r
#define LRT rt << 1
#define RRT rt << 1|1
#define BitCount(x) __builtin_popcount(x)
const double PI = acos(-1.0);
const int INF = 0x3f3f3f3f;
using namespace std;
const LL MAXN = 1e5 + 10;
const int MOD = 20071027;
typedef pair<int, int> pii;
typedef vector<int>::iterator viti;
typedef vector<pii>::iterator vitii;
int cnt[MAXN << 2];
struct SEGTREE
{
void init()
{
MS(cnt, 0);
}
void PushDown(int rt)
{
if (cnt[rt])
{
cnt[LRT] += cnt[rt];
cnt[RRT] += cnt[rt];
cnt[rt] = 0;
}
}
int search(int rt, int l, int r, int val)
{
if (l == r) return cnt[rt];
PushDown(rt);
int mid = MID(l, r);
if (val <= mid) return search(LC, val);
else return search(RC, val);
}
void update(int rt, int l, int r, int L, int R)
{
if (L <= l && r <= R)
{
cnt[rt]++;
return;
}
PushDown(rt);
int mid = MID(l, r);
if (L <= mid) update(LC, L, R);
if (R > mid) update(RC, L, R);
//PushUp(rt);
}
}segtree;
int main()
{
//ROP;
int n, i, j;
while (scanf("%d", &n), n)
{
int a, b;
segtree.init();
for (i = 0; i < n; i++)
{
scanf("%d%d", &a, &b);
segtree.update(1, 1, n, a, b);
}
for (i = 1; i <= n; i++)
if (i != n) printf("%d ", segtree.search(1, 1, n, i));
else printf("%d\n", segtree.search(1, 1, n, i));
}
return 0;
}