题目大意：给出n，k和m，用k个1~m的数组成n，问有几种组成方法。

解题思路：简单dp，cnt[i][j]表示用i个数组成j， cnt[i][j] = ∑(1 ≤ t  ≤min(k, j)) cnt[i - 1][t].

 

#include 
    
     #include 
     
      #define ll long longconst int N = 105;ll cnt[N][N];int n, k, m;void init() {	memset(cnt, 0, sizeof(cnt));	cnt[0][0] = 1;}void solve() {	init();	for (int i = 1; i <= k; i++) {		for (int j = 1; j <= n; j++) {			for (int t = 1;  t <= m && t <= j; t++)				cnt[i][j] += cnt[i - 1][j - t];		}	}		printf("%lld\n", cnt[k][n]);}int main () {	while (scanf("%d%d%d", &n, &k, &m) == 3) {		solve();	}	return 0;}