uva 757 Gone Fishing
John is going on a fishing trip. He has h hours available ( ), and there aren lakes in the area ( ) all reachable along a single, one-way road. John starts at lake 1, but he can finish at any lake he wants. He can only travel from one lake to the next one, but he does not have to stop at any lake unless he wishes to. For each, the number of 5-minute intervals it takes to travel from lakei to lake i + 1 is denoted ti ( ). For example,t3 = 4 means that it takes 20 minutes to travel from lake 3 to lake 4.
To help plan his fishing trip, John has gathered some information about the lakes. For each lakei, the number of fish expected to be caught in the initial 5 minutes, denotedfi ( ), is known. Each 5 minutes of fishing decreases the number of fish expected to be caught in the next 5-minute interval by a constant rate of di ( ). If the number of fish expected to be caught in an interval is less than or equal to di, there will be no more fish left in the lake in the next interval. To simplify the planning, John assumes that no one else will be fishing at the lakes to affect the number of fish he expects to catch.
Write a program to help John plan his fishing trip to maximize the number of fish expected to be caught. The number of minutes spent at each lake must be a multiple of 5.
InputYou will be given a number of cases in the input. Each case starts with a line containingn. This is followed by a line containing h. Next, there is a line ofn integers specifying fi ( ), then a line ofn integers di ( ), and finally, a line ofn – 1 integers ti ( ). Input is terminated by a case in whichn = 0.OutputFor each test case, print the number of minutes spent at each lake, separated by commas, for the plan achieving the maximum number of fish expected to be caught (you should print the entire plan on one line even if it exceeds 80 characters). This is followed by a line containing the number of fish expected. If multiple plans exist, choose the one that spends as long as possible at lake 1, even if no fish are expected to be caught in some intervals. If there is still a tie, choose the one that spends as long as possible at lake 2, and so on. Insert a blank line between cases.Sample Input2110 12 524410 15 20 170 3 4 31 2 34410 15 50 300 3 4 31 2 30Sample Output45, 5Number of fish expected: 31240, 0, 0, 0Number of fish expected: 480115, 10, 50, 35Number of fish expected: 724
题目大意：
每组样例包括5各部分：
1）鱼塘数 n
2）总时间 h（小时）
3）n 个鱼塘，每个鱼塘中初始鱼的产量（每5分钟可以钓上的鱼的数量）
4）n 个鱼塘，每个鱼塘鱼的损耗速度（每在该鱼塘钓鱼5分钟，鱼的产量减少的数量）
5）n 个鱼塘之间的路程的耗时（单位为5分钟）
要求在总时间 h 内可以钓上的最多的鱼的数量，和在每一个鱼塘停留的时间。当到达下一个鱼塘时，不能返回上一个鱼塘。
解题思路：先要对鱼塘之间路程的耗时进行处理，，要将其转变为从第一个鱼塘到第 i 个鱼塘所需的时间。
枚举只在前 i 个鱼塘钓鱼的 n 种情况，这样 只在前 i 个鱼塘钓鱼的钓鱼时间 = 总时间 – 第一个鱼塘到第 i 个鱼塘所需时间，然后在前 i 个鱼塘中找出当前鱼产量最多的鱼塘，在此钓鱼，然后重复之前的过程，直到前 i 个鱼塘无鱼可钓或者时间耗尽。这样，n 种情况中的最大值，就是可以钓起的最多鱼的数量。
#include<stdio.h>#include<string.h>#include<stdlib.h>#include<algorithm>using namespace std;int n, h, f[250], d[250], t[250], ans, rec[250], recA[250], temp[250];int find(int x) {int num = 0, id;for (int i = 0; i <= x; i++) {if (temp[i] > num) {num = temp[i];id = i;}}if (num) {return id;}else return -1;}int main() {int flag = 0;while (scanf("%d", &n) == 1, n) {if (flag) printf("\n");flag = 1;int H;scanf("%d", &H);h = H * 12;for (int i = 0; i < n; i++) {scanf("%d", &f[i]);}for (int i = 0; i < n; i++) {scanf("%d", &d[i]);}t[0] = 0;for (int i = 1; i < n; i++) {scanf("%d", &t[i]);t[i] += t[i – 1];}memset(recA, 0, sizeof(recA));ans = 0;for (int i = 0; i < n; i++) { //枚举n种情况：从第一个鱼塘到第i个鱼塘int time = h – t[i], sum = 0;if (time <= 0) break;memcpy(temp, f, sizeof(f));memset(rec, 0, sizeof(rec));while (time) {int id = find(i); //find找出前i个鱼塘中鱼最多的鱼塘if (id < 0) break;sum += temp[id];temp[id] -=d[id];time–;rec[id]++;}if (time > 0) { //当前i个鱼塘都无鱼可钓，且还有剩余时间，留在第一个鱼塘rec[0] += time;}if (sum > ans) {ans = sum;memcpy(recA, rec, sizeof(rec));}}if (ans) {printf("%d", recA[0] * 5);}else printf("%d", h * 5); //当无鱼可钓的时候也要停留在第一个鱼塘，样例会卡这里for (int i = 1; i < n; i++) {printf(", %d", recA[i] * 5);}printf("\nNumber of fish expected: %d\n", ans);}return 0;}
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