CodeForces 508C Anya and Ghosts
2015-08-30 20:19
316 查看
Anya and Ghosts
Time Limit:2000MS Memory Limit:262144KB 64bit IO Format:%I64d & %I64u
Submit Status Practice CodeForces 508C
Description
Anya loves to watch horror movies. In the best traditions of horror, she will be visited by m ghosts tonight. Anya has lots of candles prepared for the visits, each candle can produce light for exactly t seconds. It takes the girl one second to light one candle. More formally, Anya can spend one second to light one candle, then this candle burns for exactly t seconds and then goes out and can no longer be used.
For each of the m ghosts Anya knows the time at which it comes: the i-th visit will happen wi seconds after midnight, all wi's are distinct. Each visit lasts exactly one second.
What is the minimum number of candles Anya should use so that during each visit, at least r candles are burning? Anya can start to light a candle at any time that is integer number of seconds from midnight, possibly, at the time before midnight. That means, she can start to light a candle integer number of seconds before midnight or integer number of seconds after a midnight, or in other words in any integer moment of time.
Input
The first line contains three integers m, t, r (1 ≤ m, t, r ≤ 300), representing the number of ghosts to visit Anya, the duration of a candle's burning and the minimum number of candles that should burn during each visit.
The next line contains m space-separated numbers wi (1 ≤ i ≤ m, 1 ≤ wi ≤ 300), the i-th of them repesents at what second after the midnight the i-th ghost will come. All wi's are distinct, they follow in the strictly increasing order.
Output
If it is possible to make at least r candles burn during each visit, then print the minimum number of candles that Anya needs to light for that.
If that is impossible, print - 1.
Sample Input
Input
Output
Input
Output
Input
Output
Hint
Anya can start lighting a candle in the same second with ghost visit. But this candle isn't counted as burning at this visit.
It takes exactly one second to light up a candle and only after that second this candle is considered burning; it means that if Anya starts lighting candle at moment x, candle is buring from second x + 1 to second x + t inclusively.
In the first sample test three candles are enough. For example, Anya can start lighting them at the 3-rd, 5-th and 7-th seconds after the midnight.
In the second sample test one candle is enough. For example, Anya can start lighting it one second before the midnight.
In the third sample test the answer is - 1, since during each second at most one candle can burn but Anya needs three candles to light up the room at the moment when the ghost comes.
View Code
Time Limit:2000MS Memory Limit:262144KB 64bit IO Format:%I64d & %I64u
Submit Status Practice CodeForces 508C
Description
Anya loves to watch horror movies. In the best traditions of horror, she will be visited by m ghosts tonight. Anya has lots of candles prepared for the visits, each candle can produce light for exactly t seconds. It takes the girl one second to light one candle. More formally, Anya can spend one second to light one candle, then this candle burns for exactly t seconds and then goes out and can no longer be used.
For each of the m ghosts Anya knows the time at which it comes: the i-th visit will happen wi seconds after midnight, all wi's are distinct. Each visit lasts exactly one second.
What is the minimum number of candles Anya should use so that during each visit, at least r candles are burning? Anya can start to light a candle at any time that is integer number of seconds from midnight, possibly, at the time before midnight. That means, she can start to light a candle integer number of seconds before midnight or integer number of seconds after a midnight, or in other words in any integer moment of time.
Input
The first line contains three integers m, t, r (1 ≤ m, t, r ≤ 300), representing the number of ghosts to visit Anya, the duration of a candle's burning and the minimum number of candles that should burn during each visit.
The next line contains m space-separated numbers wi (1 ≤ i ≤ m, 1 ≤ wi ≤ 300), the i-th of them repesents at what second after the midnight the i-th ghost will come. All wi's are distinct, they follow in the strictly increasing order.
Output
If it is possible to make at least r candles burn during each visit, then print the minimum number of candles that Anya needs to light for that.
If that is impossible, print - 1.
Sample Input
Input
1 8 3 10
Output
3
Input
2 10 1 5 8
Output
1
Input
1 1 3 10
Output
-1
Hint
Anya can start lighting a candle in the same second with ghost visit. But this candle isn't counted as burning at this visit.
It takes exactly one second to light up a candle and only after that second this candle is considered burning; it means that if Anya starts lighting candle at moment x, candle is buring from second x + 1 to second x + t inclusively.
In the first sample test three candles are enough. For example, Anya can start lighting them at the 3-rd, 5-th and 7-th seconds after the midnight.
In the second sample test one candle is enough. For example, Anya can start lighting it one second before the midnight.
In the third sample test the answer is - 1, since during each second at most one candle can burn but Anya needs three candles to light up the room at the moment when the ghost comes.
#include <stdio.h> #include <string.h> int main() { int m,t,r; int w[305]; int vis[1005],lig[1005]; int i,j,flg,s,k; while(scanf("%d %d %d",&m,&t,&r)!=EOF) { flg=1;s=0; memset(lig,0,sizeof(lig)); memset(vis,0,sizeof(vis)); for(i=1;i<=m;i++) { scanf("%d",&w[i]); } if(t<r) { flg=0; } else { s=r; for(i=w[1]-1;i>=0 && i>=w[1]-r;i--) vis[i]=1; for(i=1;i<=r;i++) { for(j=w[1];j<=w[1]+t-i;j++) { lig[j]++; } } for(i=2;i<=m;i++) { if(flg==0) break; if(lig[w[i]]>=r) continue; int ww=r-lig[w[i]]; for(j=w[i]-1;j>=w[i]-ww;j--) { if(vis[j]==1) { flg=0;break; } vis[j]=1; s++; } for(k=1;k<=ww;k++) { for(j=w[i];j<=w[i]+t-k;j++) { lig[j]++; } } } } if(flg==0) printf("-1\n"); else printf("%d\n",s); } return 0; } /*for(i=0;i<=20;i++) printf("%d ",vis[i]); printf("\n"); for(i=0;i<=20;i++) printf("%d ",lig[i]); printf("\n");*/
View Code
相关文章推荐
- CodeForces 496B Secret Combination
- CodeForces 483B Friends and Presents
- Android开发详解之onTouch和onClick详解
- poj 2010 Moo University - Financial Aid(优先队列(最小堆)+ 贪心 + 枚举)
- CodeForces 490C Hacking Cypher
- virtualbox谨记:win7上只有4.3.x的版本支持ubuntu14.04.3虚拟机安装Oracle Rac,其他的版本3.x和5.0.2(至2015-08-30)均不可以
- linux 磁盘管理工具
- C语言基础知识之(十五):指针和函数
- java并发编程第六章(3)使用阻塞式线程安全列表
- ALTERA DE2 之 verilog HDL 学习笔记01 程序的并行
- Windows 多进程通信API总结
- .NET六大剑客:栈、堆、值类型、引用类型、装箱和拆箱
- 字符串最后一个单词的长度(华为在线训练)
- CodeForces 483C Diverse Permutation
- android-屏幕适配(一)
- Alien Order
- Linux进程间通信---有名管道 代码实现
- RESTEasy常用注解
- CodeForces 478C Table Decorations
- C语言基础知识之(十四):指针和字符数组、字符串数组