SRM 719 Div 1 250 500

250：

题目大意：

在一个N行无限大的网格图里，每经过一个格子都要付出一定的代价。同一行的每个格子代价相同。 给出起点和终点，求从起点到终点的付出的最少代价。

思路：

最优方案肯定是从起点沿竖直方向走到某一行，然后沿水平方向走到终点那一列，然后再沿竖直方向走到终点那一行。

枚举是通过哪一行的格子从起点那列走到终点那列的，求个最小值就好了。

代码：

// BEGIN CUT HERE

// END CUT HERE
#line 5 "OwaskiAndTree.cpp"
#include <vector>
#include <list>
#include <map>
#include <set>
#include <deque>
#include <stack>
#include <bitset>
#include <algorithm>
#include <functional>
#include <numeric>
#include <utility>
#include <sstream>
#include <iostream>
#include <iomanip>
#include <cstdio>
#include <cmath>
#include <cstdlib>
#include <ctime>
#include <cstring>
using namespace std;
class OwaskiAndTree
{
public:
int maximalScore(vector <int> parent, vector <int> pleasure)
{
//$CARETPOSITION$
int n = pleasure.size();
long long a[1010] = {0}, b[1010] = {0};
for (int i = n - 1; i >= 0; --i)
{
a[i] += pleasure[i];
a[i] = max(a[i], 0ll);
b[i] = max(b[i], a[i]);

if (i == 0) continue;
int u = parent[i - 1];
a[u] += max(a[i], 0ll);
b[u] += b[i];
}
return b[0];
}

// BEGIN CUT HERE
public:
void run_test(int Case) { if ((Case == -1) || (Case == 0)) test_case_0(); if ((Case == -1) || (Case == 1)) test_case_1(); if ((Case == -1) || (Case == 2)) test_case_2(); if ((Case == -1) || (Case == 3)) test_case_3(); if ((Case == -1) || (Case == 4)) test_case_4(); }
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 int &Expected, const int &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 Arr0[] = {0, 1, 2, 3, 4, 5, 6, 7, 8}; vector <int> Arg0(Arr0, Arr0 + (sizeof(Arr0) / sizeof(Arr0[0]))); int Arr1[] = {1, 1, -1, -1, -1, -1, 1, 1, 1, 1}; vector <int> Arg1(Arr1, Arr1 + (sizeof(Arr1) / sizeof(Arr1[0]))); int Arg2 = 4; verify_case(0, Arg2, maximalScore(Arg0, Arg1)); }
void test_case_1() { int Arr0[] = {0, 0, 1, 2}; vector <int> Arg0(Arr0, Arr0 + (sizeof(Arr0) / sizeof(Arr0[0]))); int Arr1[] = {2, 3, 4, -1, -1}; vector <int> Arg1(Arr1, Arr1 + (sizeof(Arr1) / sizeof(Arr1[0]))); int Arg2 = 9; verify_case(1, Arg2, maximalScore(Arg0, Arg1)); }
void test_case_2() { int Arr0[] = {0, 0, 1, 1, 2, 2, 5, 5}; vector <int> Arg0(Arr0, Arr0 + (sizeof(Arr0) / sizeof(Arr0[0]))); int Arr1[] = {1, 2, -3, -7, 3, 2, 7, -1, 3}; vector <int> Arg1(Arr1, Arr1 + (sizeof(Arr1) / sizeof(Arr1[0]))); int Arg2 = 17; verify_case(2, Arg2, maximalScore(Arg0, Arg1)); }
void test_case_3() { int Arr0[] = {0, 1, 1, 1, 0, 3, 1, 3, 4, 4, 3, 6, 8, 0, 12, 12, 11, 7, 7}; vector <int> Arg0(Arr0, Arr0 + (sizeof(Arr0) / sizeof(Arr0[0]))); int Arr1[] = {-154011, 249645, 387572, 292156, -798388, 560085, -261135, -812756, 191481, -165204, 81513, -448791, 608073, 354614, -455750, 325999, 227225, -696501, 904692, -297238}; vector <int> Arg1(Arr1, Arr1 + (sizeof(Arr1) / sizeof(Arr1[0]))); int Arg2 = 3672275; verify_case(3, Arg2, maximalScore(Arg0, Arg1)); }
void test_case_4() { int Arr0[] = {}; vector <int> Arg0(Arr0, Arr0 + (sizeof(Arr0) / sizeof(Arr0[0]))); int Arr1[] = {-1}; vector <int> Arg1(Arr1, Arr1 + (sizeof(Arr1) / sizeof(Arr1[0]))); int Arg2 = 0; verify_case(4, Arg2, maximalScore(Arg0, Arg1)); }

// END CUT HERE

};

// BEGIN CUT HERE
int main()
{
OwaskiAndTree ___test;
___test.run_test(-1);
system("pause");
}
// END CUT HERE

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