Add Unbounded knapsack in C code (#832)

* Update vector.h

增加功能列表:
获取向量的第 i 个元素
设置向量的第 i 个元素
向量扩容
向量缩容
向量插入元素
向量删除元素
向量交换元素
向量是否为空
向量是否已满
向量是否相等
对向量内部进行排序(升序/降序)
对向量某段数据排序(升序/降序)

* Create hanota.c

* 新增binary_search_recur.c

* Update vector.h

* Delete codes/c/chapter_divide_and_conquer directory

* Update vector.h

* Create binary_search_recur.c

* Delete codes/chapter_divide_and_conquer directory

* Update vector.h

* old vector.h

* Create unbounded_knapsack.c

* Update unbounded_knapsack.c

* Update unbounded_knapsack.c

* Create CMakeLists.txt

* Update unbounded_knapsack.c

---------

Co-authored-by: Yudong Jin <krahets@163.com>
This commit is contained in:
王作勋 2023-10-07 21:38:02 +08:00 committed by GitHub
parent 1364bc52e7
commit d75a2eb691
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2 changed files with 74 additions and 1 deletions

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@ -1,3 +1,4 @@
add_executable(min_cost_climbing_stairs_dp min_cost_climbing_stairs_dp.c)
add_executable(min_path_sum min_path_sum.c)
add_executable(knapsack knapsack.c)
add_executable(min_cost_climbing_stairs_dp min_cost_climbing_stairs_dp.c)
add_executable(unbounded_knapsack unbounded_knapsack.c)

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/**
* File: unbounded_knapsack.c
* Created Time: 2023-10-02
* Author: Zuoxun (845242523@qq.com)
*/
#include "../utils/common.h"
/* 求最大值 */
int max(int a, int b) {
return a > b ? a : b;
}
/* 完全背包:动态规划 */
int unboundedKnapsackDP(int wgt[], int val[], int cap, int wgtSize) {
int n = wgtSize;
// 初始化 dp 表
int dp[n + 1][cap + 1];
memset(dp, 0, sizeof(dp));
// 状态转移
for (int i = 1; i <= n; i++) {
for (int c = 1; c <= cap; c++) {
if (wgt[i - 1] > c) {
// 若超过背包容量,则不选物品 i
dp[i][c] = dp[i - 1][c];
} else {
// 不选和选物品 i 这两种方案的较大值
dp[i][c] = max(dp[i - 1][c], dp[i][c - wgt[i - 1]] + val[i - 1]);
}
}
}
return dp[n][cap];
}
/* 完全背包:空间优化后的动态规划 */
int unboundedKnapsackDPComp(int wgt[], int val[], int cap, int wgtSize) {
int n = wgtSize;
// 初始化 dp 表
int dp[cap + 1];
memset(dp, 0, sizeof(dp));
// 状态转移
for (int i = 1; i <= n; i++) {
for (int c = 1; c <= cap; c++) {
if (wgt[i - 1] > c) {
// 若超过背包容量,则不选物品 i
dp[c] = dp[c];
} else {
// 不选和选物品 i 这两种方案的较大值
dp[c] = max(dp[c], dp[c - wgt[i - 1]] + val[i - 1]);
}
}
}
return dp[cap];
}
/* Driver code */
int main() {
int wgt[] = {1, 2, 3};
int val[] = {5, 11, 15};
int wgtSize = sizeof(wgt) / sizeof(wgt[0]);
int cap = 4;
// 动态规划
int res = unboundedKnapsackDP(wgt, val, cap, wgtSize);
printf("不超过背包容量的最大物品价值为 %d\n", res);
// 空间优化后的动态规划
res = unboundedKnapsackDPComp(wgt, val, cap, wgtSize);
printf("不超过背包容量的最大物品价值为 %d\n", res);
return 0;
}