[数学 二分图匹配] SRM 456 div1 FunctionalEquation

本来想自己再推一下的，但是退役了也就弃坑了
未经允许的搬了搬题人的题解

// BEGIN CUT HERE  #include<conio.h>#include<sstream>// END CUT HERE  #include<cstdio>#include<cstdlib>#include<cstring>#include<cmath>#include<iostream>#include<algorithm>#include<vector>#include<map>#include<string>#include<set>#define pb push_back#define cl(x) memset(x,0,sizeof(x))using namespace std;typedef long long ll;const int N=10005;const int CC=16;int n,C;int x[N],y[N];vector<int> v[(CC+5)<<1];ll W[N]; int pnt=0;inline ll calc(ll x){  ll ret=0; for (int i=1;i<=pnt;i++) ret+=abs(W[i]-x); return ret;}ll w[CC+5][CC+5];ll f[CC+5][1<<CC];class FunctionalEquation{public:  long long minAbsSum(int C, int n, int x0, int xp, int xa, int xm, int y0, int yp, int ya, int ym){    x[1]=x0; y[1]=y0; v[x[1]%(2*C)].pb(1);    for (int i=2;i<=n;i++){      x[i]=((ll)x[i-1]*xp+xa)%xm,y[i]=((ll)y[i-1]*yp+ya)%ym;      v[x[i]%(2*C)].pb(i);    }    for (int x=0;x<C;x++)      for (int y=0;y<C;y++){    int a=x<<1,b=y<<1|1;    pnt=0;    for (int i:v[a])      W[++pnt]=x+y+(::x[i]-a)-::y[i];    for (int i:v[b])      W[++pnt]=-x-y-(::x[i]-b)-C+::y[i];    ll ret=1LL<<60;    sort(W+1,W+pnt+1);    int mid=(pnt+1)>>1,t=W[mid]/C;    for (int i=t-5;i<=t+5;i++)      ret=min(ret,calc((ll)i*C));    w[x+1][y+1]=ret;      }    memset(f,0x3f,sizeof(f));    f[0][0]=0;    for (int i=0;i<C;i++)      for (int s=0;s<(1<<C);s++)    for (int j=1;j<=C;j++)      if (~s>>(j-1)&1)        f[i+1][s|(1<<(j-1))]=min(f[i+1][s|(1<<(j-1))],f[i][s]+w[i+1][j]);    return f[C][(1<<C)-1];  }  // BEGIN CUT HEREpublic:  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(); }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 = 3; int Arg1 = 10; int Arg2 = 0; int Arg3 = 1; int Arg4 = 1; int Arg5 = 456; int Arg6 = 1; int Arg7 = 1; int Arg8 = 1; int Arg9 = 456; long long Arg10 = 0LL; verify_case(0, Arg10, minAbsSum(Arg0, Arg1, Arg2, Arg3, Arg4, Arg5, Arg6, Arg7, Arg8, Arg9)); }  void test_case_1() { int Arg0 = 4; int Arg1 = 10; int Arg2 = 0; int Arg3 = 1; int Arg4 = 1; int Arg5 = 456; int Arg6 = 1; int Arg7 = 1; int Arg8 = 1; int Arg9 = 456; long long Arg10 = 5LL; verify_case(1, Arg10, minAbsSum(Arg0, Arg1, Arg2, Arg3, Arg4, Arg5, Arg6, Arg7, Arg8, Arg9)); }  void test_case_2() { int Arg0 = 16; int Arg1 = 10000; int Arg2 = 654816386; int Arg3 = 163457813; int Arg4 = 165911619; int Arg5 = 987654321; int Arg6 = 817645381; int Arg7 = 871564816; int Arg8 = 614735118; int Arg9 = 876543210; long long Arg10 = 3150803357206LL; verify_case(2, Arg10, minAbsSum(Arg0, Arg1, Arg2, Arg3, Arg4, Arg5, Arg6, Arg7, Arg8, Arg9)); }  // END CUT HERE};// BEGIN CUT HEREint main(){  FunctionalEquation ___test;  ___test.run_test(-1);  getch() ;  return 0;}// END CUT HERE