SRM 395(1-250pt)

DIV1 250pt

题意：在平面直角坐标系中，只能走到整点，每次有两种移动方法，可以沿平行于坐标轴方向走，也可以沿45度方向走，前者走一步耗时wt，后者走一步耗时st。比如从(x, y)可以走到(x+1, y)，(x-1, y)，(x, y+1)，(x, y-1)四个点，耗时均为wt，也可以走到(x-1, y+1)，(x-1, y-1)，(x+1, y+1)，(x+1, y-1)，耗时均为st。给定x, y, wt, st，求从(0, 0)到(x, y)最少耗时多少。

解法：水题，见代码。

tag: greedy

 // BEGIN CUT HERE

 /*

 */

 // END CUT HERE

 #line 7 "StreetWalking.cpp"

 #include <cstdlib>

 #include <cctype>

 #include <cstring>

 #include <cstdio>

 #include <cmath>

 #include <algorithm>

 #include <vector>

 #include <iostream>

 #include <sstream>

 #include <set>

 #include <queue>

 #include <fstream>

 #include <numeric>

 #include <iomanip>

 #include <bitset>

 #include <list>

 #include <stdexcept>

 #include <functional>

 #include <string>

 #include <utility>

 #include <map>

 #include <ctime>

 #include <stack>

 using namespace std;

 #define clr0(x) memset(x, 0, sizeof(x))

 #define clr1(x) memset(x, -1, sizeof(x))

 #define pb push_back

 #define mp make_pair

 #define sz(v) ((int)(v).size())

 #define out(x) cout<<#x<<":"<<(x)<<endl

 #define tst(a) cout<<#a<<endl

 #define CINBEQUICKER std::ios::sync_with_stdio(false)

 typedef vector<int> VI;

 typedef vector<string> VS;

 typedef vector<double> VD;

 typedef long long int64;

 const double eps = 1e-;

 const double PI = atan(1.0)*;

 const int inf =  / ;

 inline int MyMod( int a , int b ) { return (a%b+b)%b;}

 class StreetWalking

 {

     public:

         long long minTime(int x, int y, int wt, int st){

             if (st >= wt*) return ((int64)x + y) * wt;

             if (x < y) swap(x, y);

             int64 t = (int64)y * st;

             int64 dif = x - y;

             if (st < wt){

                 if (dif & ) return t + (dif-) * st + wt;

                 return t + dif * st;

             }

             return t + dif * wt;

         }

 // BEGIN CUT HERE

     public:

     void run_test(int Case) { if ((Case == -) || (Case == )) test_case_0(); if ((Case == -) || (Case == )) test_case_1(); if ((Case == -) || (Case == )) test_case_2(); if ((Case == -) || (Case == )) test_case_3(); if ((Case == -) || (Case == )) test_case_4(); if ((Case == -) || (Case == )) test_case_5(); if ((Case == -) || (Case == )) test_case_6(); }

     private:

     template <typename T> string print_array(const vector<T> &V) { ostringstream os; os << "{ "; for (typename vector<T>::const_iterator iter = V.begin(); iter != V.end(); ++iter) os << '\"' << *iter << "\","; os << " }"; return os.str(); }

     void verify_case(int Case, const long long &Expected, const long long &Received) { cerr << "Test Case #" << Case << "..."; if (Expected == Received) cerr << "PASSED" << endl; else { cerr << "FAILED" << endl; cerr << "\tExpected: \"" << Expected << '\"' << endl; cerr << "\tReceived: \"" << Received << '\"' << endl; } }

     void test_case_0() { int Arg0 = ; int Arg1 = ; int Arg2 = ; int Arg3 = ; long long Arg4 = 18LL; verify_case(, Arg4, minTime(Arg0, Arg1, Arg2, Arg3)); }

     void test_case_1() { int Arg0 = ; int Arg1 = ; int Arg2 = ; int Arg3 = ; long long Arg4 = 16LL; verify_case(, Arg4, minTime(Arg0, Arg1, Arg2, Arg3)); }

     void test_case_2() { int Arg0 = ; int Arg1 = ; int Arg2 = ; int Arg3 = ; long long Arg4 = 20LL; verify_case(, Arg4, minTime(Arg0, Arg1, Arg2, Arg3)); }

     void test_case_3() { int Arg0 = ; int Arg1 = ; int Arg2 = ; int Arg3 = ; long long Arg4 = 247LL; verify_case(, Arg4, minTime(Arg0, Arg1, Arg2, Arg3)); }

     void test_case_4() { int Arg0 = ; int Arg1 = ; int Arg2 = ; int Arg3 = ; long long Arg4 = 240LL; verify_case(, Arg4, minTime(Arg0, Arg1, Arg2, Arg3)); }

     void test_case_5() { int Arg0 = ; int Arg1 = ; int Arg2 = ; int Arg3 = ; long long Arg4 = 41010000000LL; verify_case(, Arg4, minTime(Arg0, Arg1, Arg2, Arg3)); }

     void test_case_6() { int Arg0 = ; int Arg1 = ; int Arg2 = ; int Arg3 = ; long long Arg4 = 3929LL; verify_case(, Arg4, minTime(Arg0, Arg1, Arg2, Arg3)); }

 // END CUT HERE

 };

 //by plum rain

 // BEGIN CUT HERE

 int main()

 {

     //freopen( "a.out" , "w" , stdout );

     StreetWalking ___test;

     ___test.run_test(-);

        return ;

 }

 // END CUT HERE