http://uva.onlinejudge.org/index.php?option=com_onlinejudge&Itemid=8&page=show_problem&problem=83php
Time limit: 3.000 secondshtml
New Zealand currency consists of $100, $50, $20, $10, and $5 notes and $2, $1, 50c, 20c, 10c and 5c coins. Write a program that will determine, for any given amount, in how many ways that amount may be made up. Changing the order of listing does not increase the count. Thus 20c may be made up in 4 ways: 1 20c, 2 10c, 10c+2 5c, and 4 5c.ios
Input will consist of a series of real numbers no greater than $300.00 each on a separate line. Each amount will be valid, that is will be a multiple of 5c. The file will be terminated by a line containing zero (0.00).ide
Output will consist of a line for each of the amounts in the input, each line consisting of the amount of money (with two decimal places and right justified in a field of width 6), followed by the number of ways in which that amount may be made up, right justified in a field of width 17.spa
0.20 2.00 0.00
0.20 4 2.00 293
分析:code
這個題跟UVA674題相似,只是這個題有更多的錢的種類,而且須要用long long來保存htm
作的方法是先乘以100消除浮點數的偏差,而後計算,須要注意的是輸出格式有要求,有特殊的空格要求~blog
AC代碼:ip
遞推:ci
1 #include<cstdio> 2 #include<cstring> 3 #include<iostream> 4 using namespace std; 5 const int maxn=30001; 6 int num[12]={0,5,10,20,50,100,200,500,1000,2000,5000,10000}; 7 int a,b; 8 long long f[maxn][12]; 9 void Init() 10 { 11 for(int i=0;i<12;i++) 12 f[0][i]=1; 13 for(int i=1;i<maxn;i++) 14 for(int j=1;j<12;j++) 15 for(int k=0;num[j]*k<=i;k++) 16 f[i][j]+=f[i-num[j]*k][j-1]; 17 } 18 int main() 19 { 20 Init(); 21 while(scanf("%d.%d",&a,&b)&&(a+b)) 22 { 23 int n=a*100+b; 24 printf("%6.2lf%17lld\n",n*1.0/100,f[n][11]); 25 } 26 return 0; 27 }
揹包:
1 #include<cstdio> 2 #include<cstring> 3 #include<iostream> 4 using namespace std; 5 const int maxn=30001; 6 int num[12]={0,5,10,20,50,100,200,500,1000,2000,5000,10000}; 7 int a,b; 8 long long f[maxn][12]; 9 void Init() 10 { 11 for(int i=0;i<12;i++) 12 f[0][i]=1; 13 for(int i=1;i<maxn;i++) 14 for(int j=1;j<12;j++) 15 for(int k=0;num[j]*k<=i;k++) 16 f[i][j]+=f[i-num[j]*k][j-1]; 17 } 18 int main() 19 { 20 Init(); 21 while(scanf("%d.%d",&a,&b)&&(a+b)) 22 { 23 int n=a*100+b; 24 printf("%6.2lf%17lld\n",n*1.0/100,f[n][11]); 25 } 26 return 0; 27 }
後來想到能夠再除以5(題目說是5的倍數),來減小運算量,提升運算效率。
1 #include <cstdio> 2 using namespace std; 3 4 long long f[30010]; 5 const int num[] = {2000, 1000, 400, 200, 100, 40, 20, 10, 4, 2, 1}; 6 7 int main() 8 { 9 f[0] = 1; 10 for(int i = 0 ;i <= 10;i ++) 11 for(int j = num[i] ;j <= 6005;j ++) 12 f[j] += f[j - num[i]]; 13 double x; 14 while(scanf("%lf", &x) , x) 15 { 16 double tx = x * 20; 17 printf("%6.2lf%17lld\n", x , f[(int)tx] ); 18 } 19 return 0; 20 }