用C语言写一个解决01背包问题的程序，程序会输入一个文件，要求如下：The input txt file has 3 lines. The first line has only one integer, the capacity of the bag. The second line has a bunch of positive integers for the value of each item. Two integers are separated by a comma “,”. The third line is in the same format as the second for the weight of each item. - When the calculation is finished, print the optimal value and optimal solution(s) one for each line on the screen. (The optimal value is unique, but the optimal solution may not.) - Sort the items in the optimal solution(s) in the decreasing order of item indices. - The index of items starts from 1.

以下是用C语言实现01背包问题的程序：

#include <stdio.h>
#include <stdlib.h>

#define MAX_N 100
#define MAX_W 1000

int n, W, w[MAX_N], v[MAX_N];
int dp[MAX_N + 1][MAX_W + 1];

void solve() {
    int i, j;
    for (i = 0; i < n; i++) {
        for (j = 0; j <= W; j++) {
            if (j < w[i]) {
                dp[i + 1][j] = dp[i][j];
            } else {
                dp[i + 1][j] = (dp[i][j] > dp[i][j - w[i]] + v[i]) ? dp[i][j] : dp[i][j - w[i]] + v[i];
            }
        }
    }
}

void print_solution(int i, int j, int* sol) {
    if (i == 0) {
        return;
    }
    if (dp[i][j] == dp[i - 1][j]) {
        print_solution(i - 1, j, sol);
    } else {
        sol[i - 1] = 1;
        print_solution(i - 1, j - w[i - 1], sol);
    }
}

int main() {
    int i, j;
    scanf("%d", &W);
    n = 0;
    while (scanf(",%d", &v[n]) != EOF) {
        n++;
    }
    for (i = 0; i < n; i++) {
        scanf(",%d", &w[i]);
    }
    solve();
    printf("%d\n", dp[n][W]);
    int* sol = (int*)malloc(n * sizeof(int));
    for (i = 0; i < n; i++) {
        sol[i] = 0;
    }
    print_solution(n, W, sol);
    int flag = 1;
    for (i = 0; i < n; i++) {
        if (sol[i]) {
            if (flag) {
                flag = 0;
            } else {
                printf(",");
            }
            printf("%d", i + 1);
        }
    }
    printf("\n");
    free(sol);
    return 0;
}

程序使用动态规划求解01背包问题，时间复杂度为O(nW)，其中n为物品数量，W为背包容量。程序从标准输入中读入数据，第一行为背包容量W，第二行为物品的价值，每个整数之间用逗号分隔，第三行为物品的重量，也是用逗号分隔的整数。程序输出最优解和最优解的方案，每个输出用一个换行符分隔。最优解的格式为一个整数，表示最大价值；最优解的方案的格式为逗号分隔的整数，表示所选择的物品的编号。