NOOJ927The partial sum problem

题目链接：http://acm.nyist.net/JudgeOnline/problem.php?pid=927

这也算是个0-1背包的思想的吧。加上剪枝。

代码：

#include <cstdio>#include <algorithm>#include <cstring>using namespace std;int n,k;int a[25];bool dfs(int cur,int sum){    if(sum > k)        return false;    if(sum == k)        return true;    if(cur == n)        return sum == k;    if(dfs(cur + 1,sum))        return true;    if(dfs(cur + 1,sum + a[cur]))        return true;}int main(){    while(~scanf("%d",&n))    {        for(int i = 0; i < n; ++i)            scanf("%d",&a[i]);        scanf("%d",&k);        if(dfs(0,0))            printf("Of course,I can!\n");        else            printf("Sorry,I can't!\n");    }}