poj1018
2012-07-13 23:17
197 查看
Communication System
Description
We have received an order from Pizoor Communications Inc. for a special communication system. The system consists of several devices. For each device, we are free to choose from several manufacturers. Same devices from two manufacturers differ in their maximum
bandwidths and prices.
By overall bandwidth (B) we mean the minimum of the bandwidths of the chosen devices in the communication system and the total price (P) is the sum of the prices of all chosen devices. Our goal is to choose a manufacturer for each device to maximize B/P.
Input
The first line of the input file contains a single integer t (1 ≤ t ≤ 10), the number of test cases, followed by the input data for each test case. Each test case starts with a line containing a single integer n (1 ≤ n ≤ 100), the number of devices in the communication
system, followed by n lines in the following format: the i-th line (1 ≤ i ≤ n) starts with mi (1 ≤ mi ≤ 100), the number of manufacturers for the i-th device, followed by mi pairs of positive integers in the same line, each indicating the bandwidth and the
price of the device respectively, corresponding to a manufacturer.
Output
Your program should produce a single line for each test case containing a single number which is the maximum possible B/P for the test case. Round the numbers in the output to 3 digits after decimal point.
Sample Input
Sample Output
Source
Tehran 2002, First Iran Nationwide Internet Programming Contest
Description
We have received an order from Pizoor Communications Inc. for a special communication system. The system consists of several devices. For each device, we are free to choose from several manufacturers. Same devices from two manufacturers differ in their maximum
bandwidths and prices.
By overall bandwidth (B) we mean the minimum of the bandwidths of the chosen devices in the communication system and the total price (P) is the sum of the prices of all chosen devices. Our goal is to choose a manufacturer for each device to maximize B/P.
Input
The first line of the input file contains a single integer t (1 ≤ t ≤ 10), the number of test cases, followed by the input data for each test case. Each test case starts with a line containing a single integer n (1 ≤ n ≤ 100), the number of devices in the communication
system, followed by n lines in the following format: the i-th line (1 ≤ i ≤ n) starts with mi (1 ≤ mi ≤ 100), the number of manufacturers for the i-th device, followed by mi pairs of positive integers in the same line, each indicating the bandwidth and the
price of the device respectively, corresponding to a manufacturer.
Output
Your program should produce a single line for each test case containing a single number which is the maximum possible B/P for the test case. Round the numbers in the output to 3 digits after decimal point.
Sample Input
1 3 3 100 25 150 35 80 25 2 120 80 155 40 2 100 100 120 110
Sample Output
0.649
Source
Tehran 2002, First Iran Nationwide Internet Programming Contest
#include<iostream> #include<cstring> #include<iomanip> using namespace std; int device[101][1001]; int main(void) { int t; cin >> t; while (t--) { memset(device, 0x7f, sizeof (device)); for (int i = 0; i < 1001; i++) device[0][i] = 0; int n; cin >> n; for (int i = 1; i <= n; i++) { int m; cin >> m; while (m--) { int b; int p; cin >> b >> p; for (int j = 1; j <= b; j++) if (device[i - 1][j] + p < device[i][j]) device[i][j] = device[i - 1][j] + p; } } double t = 0.0; for (int i = 0; i < 1001; i++) if (1.0 * i / device [i] > t) t = 1.0 * i / device [i]; cout << fixed << setprecision(3) << t << endl; } }
相关文章推荐
- POJ 3660 Cow Contest / HUST 1037 Cow Contest / HRBUST 1018 Cow Contest(图论,传递闭包)
- POJ 1018 Communication System
- POJ_1018_Communication System
- poj 1018 Communication System
- poj 1018 Communication System
- 【dp】poj 1018 Communication System
- poj 1018
- POJ1018-Communication System
- POJ 1018 Communication System(二维DP)
- poj 1018
- POJ 1018--Communication System
- poj 1018 Communication System (dp | 贪心)
- POJ 1018(多关键字排序还在wa…)
- POJ 1018 Communication System 贪心+枚举
- POJ 1018 Communication System 题解
- POJ1018解题报告
- poj1018
- poj 1018 Communication System
- POJ1018-Communication System
- POJ 1018 Communication System