Fruit

2 3
1 2
1 2
3 5
0 3
0 3
0 3

2
12

简单母函数。

代码：

#include <iostream>
#include <cstdio>
#include <cstring>
#include <algorithm>
#include <queue>
using namespace std;
const int M = 1e5+10;

int c1[101], c2[101];
int x[M], y[M];

int main(){
    int n, m;
    while(cin >> n >> m){
        for(int i = 0; i < n; ++ i)
            cin >> x[i] >> y[i];
        memset(c1, 0, sizeof(c1));
        memset(c2, 0, sizeof(c2));
        c1[0] = 1;
        for(int i = 0; i < n; ++ i){
            for(int j = x[i]; j <= y[i]&&j <= m; ++ j){
                for(int k = 0; k+j <= m; ++ k){
                    c2[k+j] += c1[k];
                }
            }
            for(int j = 0; j <= m; ++ j){
                c1[j] = c2[j]; c2[j] = 0;
            }
        }
        cout << c1[m]<<endl;
    }
    return 0;
}

Hdoj 2152 Fruit 【母函数】

原文：http://blog.csdn.net/shengweisong/article/details/44539313