E. Let's Go Rolling!
http://codeforces.com/problemset/problem/38/E
DP状态很容易想到,以后超long long 最大值的设定最好计算出一个边界, int_max的边界赋值 错误,导致WA那么多次。
![](https://images.cnblogs.com/OutliningIndicators/ContractedBlock.gif)
#include <iostream> #include <cstdio> #include <vector> #include <cmath> #include <set> #include <map> #include <queue> #include <fstream> #include <string> #include <cstring> #include <algorithm> typedef __int64 int64; //typedef long long int64; const __int64 int_max = 10000000000000; //#define int_max 0x3f3f3f3f int64 f_min(int64 x,int64 y) {if(x<y)return x; else return y;} int f_max(int x,int y) {if(x<y)return y; else return x;} void swap(int&x,int&y) {x=x^y;y=x^y;x=x^y;} int64 f_abs(int64 x) {return (x)>(0)?(x):(-x);} int lowbit(int x) {return (x)&(-x);} bool isdig(char ch) {return ch>='0' && ch<='9';} //double f_min(double x,double y) {if(x<y)return x; else return y;} //double f_max(double x,double y) {if(x<y)return y; else return x;} using namespace std; const int MM = 22222; #define mod 10000000000 const double Pi = acos(-1.0); const double lep = 1e-10; const double inf = 1000000000.00; #define debug puts("wrong") #define lson rt<<1 #define rson rt<<1|1 int dx[8]={1,2,1,2,-1,-2,-1,-2}; int dy[8]={2,1,-2,-1,2,1,-2,-1}; int64 N,M, Q; int NE; struct Pos { int64 x,c; bool operator<(Pos a) const { return x<a.x; } }p[MM]; void get_data() { int64 i,j,k; for(i=1;i<=N;i++) { scanf("%I64d%I64d",&p[i].x,&p[i].c); } sort(p+1,p+N+1); } int64 dp[MM][2]; void solve() { int64 i,j,k,tmp,sum; dp[0][0]=dp[0][1]=0; dp[1][1]=p[1].c; dp[1][0]=int_max; for(i=2;i<=N;i++) { dp[i][0]=dp[i][1]=int_max; sum=0; tmp=1; for(j=i-1;j>0;j--) { sum=sum+(p[j+1].x-p[j].x)*tmp; dp[i][0]=f_min(dp[i][0],dp[j][1]+sum); if(p[j+1].x==p[j].x) while(1); tmp++; } dp[i][1]=f_min(dp[i-1][0],dp[i-1][1])+p[i].c; // printf("%I64d %I64d %I64d\n",i,dp[i][0],dp[i][1]); } int64 ans=f_min(dp[N][0],dp[N][1]); printf("%I64d\n",ans); } int main() { // freopen("input.txt","r",stdin); // freopen("output.txt","w",stdout); while(scanf("%I64d",&N)!=EOF) get_data(),solve(); return 0; }