[动态规划]UVA357 - Let Me Count The Ways

2014-11-24 11:56:10 · 作者: · 浏览: 1


Let Me Count The Ways

After making a purchase at a large department store, Mel's change was 17 cents. He received 1 dime, 1 nickel, and 2 pennies. Later that day, he was shopping at a convenience store. Again his change was 17 cents. This time he received 2 nickels and 7 pennies. He began to wonder ' "How many stores can I shop in and receive 17 cents change in a different configuration of coins After a suitable mental struggle, he decided the answer was 6. He then challenged you to consider the general problem.

Write a program which will determine the number of different combinations of US coins (penny: 1c, nickel: 5c, dime: 10c, quarter: 25c, half-dollar: 50c) which may be used to produce a given amount of money.

Input

The input will consist of a set of numbers between 0 and 30000 inclusive, one per line in the input file.

Output

The output will consist of the appropriate statement from the selection below on a single line in the output file for each input value. The number m is the number your program computes, n is the input value.

There are m ways to produce n cents change.

There is only 1 way to produce n cents change.

Sample input

17 
11
4

Sample output

There are 6 ways to produce 17 cents change. 
There are 4 ways to produce 11 cents change. 
There is only 1 way to produce 4 cents change.

题意:

经过在百货公司的一场血拼之后,小梅发现她身上的零钱共有17分(cent,美金货币单位,其他货币及面值请参考下方红字部分),分别是1个dime,1个nickel,以及2个penny。隔天,小梅去便利商店买完东西后发现她身上的零钱恰好又是17分,这次是2个nickel及7个penny。小梅就在想,有几种硬币的组合可能凑成17分呢?经过仔细算算之后,发现共有6种。

你的问题就是:给一个金额,请你回答共有多少种硬币组合的方式。

思路:动态规划的水题目,又是换硬币这一类型的题目。

#include
  
   
#include
   
     using namespace std; const int maxn=30010; int val[]={1,5,10,25,50}; long long dp[maxn]; int main() { int i,j; memset(dp,0,sizeof(dp)); dp[0]=1; for(i=0;i<5;i++) { for(j=val[i];j<=maxn;j++) { dp[j]=dp[j]+dp[j-val[i]]; } } int cnt; while(cin>>cnt) { if(dp[cnt]>1) cout<<"There are "<