C语言实现：计算n个元素集合的非空子集划分数量

```c #include <stdio.h> int countPartitions(int n) { int dp[n + 1]; dp[0] = 0; dp[1] = 1; for (int i = 2; i <= n; i++) { dp[i] = 2 * dp[i - 1]; for (int j = 1; j < i; j++) { dp[i] += dp[j] * dp[i - j]; } } return dp[n]; } int main() { FILE *fin = fopen("input.txt", "r"); FILE *fout = fopen("output.txt", "w"); int n; fscanf(fin, "%d", &n); int result = countPartitions(n); fprintf(fout, "%d", result); fclose(fin); fclose(fout); return 0; } ``` ######[AI问答 | 223点数解答 | 2025-04-02 08:32:25]