hdu 5970 最大公约数

传送门：http://acm.hdu.edu.cn/showproblem.php?pid=5970

∑i=1n∑j=1m⌊(i∗j)f(i,j)⌋=∑j=1m∑i=1j∑k=0c−1∑l=0i+j∗(k+l∗c)<=n⌊(i+j∗(k+l∗c))c∗x∗x⌋=∑j=1m∑i=1j∑k=0c−1∑l=0i+j∗(k+l∗c)<=n⌊(i+j∗k)∗jc∗x∗x⌋+l∗j∗jx∗x

//china no.1#pragma comment(linker, "/STACK:1024000000,1024000000")#include <vector>#include <iostream>#include <string>#include <map>#include <stack>#include <cstring>#include <queue>#include <list>#include <stdio.h>#include <set>#include <algorithm>#include <cstdlib>#include <cmath>#include <iomanip>#include <cctype>#include <sstream>#include <functional>#include <stdlib.h>#include <time.h>#include <bitset>using namespace std;#define pi acos(-1)#define s_1(x) scanf("%d",&x)#define s_2(x,y) scanf("%d%d",&x,&y)#define s_3(x,y,z) scanf("%d%d%d",&x,&y,&z)#define PI acos(-1)#define endl '\n'#define srand() srand(time(0));#define me(x,y) memset(x,y,sizeof(x));#define foreach(it,a) for(__typeof((a).begin()) it=(a).begin();it!=(a).end();it++)#define close() ios::sync_with_stdio(0); cin.tie(0);#define FOR(x,n,i) for(int i=x;i<=n;i++)#define FOr(x,n,i) for(int i=x;i<n;i++)#define fOR(n,x,i) for(int i=n;i>=x;i--)#define fOr(n,x,i) for(int i=n;i>x;i--)#define W while#define sgn(x) ((x) < 0 ? -1 : (x) > 0)#define bug printf("***********\n");#define db double#define ll long long#define mp make_pair#define pb push_backtypedef pair<long long int,long long int> ii;typedef long long LL;const int INF=0x3f3f3f3f;const LL LINF=0x3f3f3f3f3f3f3f3fLL;const int dx[]={-1,0,1,0,1,-1,-1,1};const int dy[]={0,1,0,-1,-1,1,-1,1};const int maxn=1e3+10;const int maxx=600005;const double EPS=1e-8;const double eps=1e-8;const int mod=1e9+7;template<class T>inline T min(T a,T b,T c) { return min(min(a,b),c);}template<class T>inline T max(T a,T b,T c) { return max(max(a,b),c);}template<class T>inline T min(T a,T b,T c,T d) { return min(min(a,b),min(c,d));}template<class T>inline T max(T a,T b,T c,T d) { return max(max(a,b),max(c,d));}template <class T>inline bool scan_d(T &ret){char c;int sgn;if (c = getchar(), c == EOF){return 0;}while (c != '-' && (c < '0' || c > '9')){c = getchar();}sgn = (c == '-') ? -1 : 1;ret = (c == '-') ? 0 : (c - '0');while (c = getchar(), c >= '0' && c <= '9'){ret = ret * 10 + (c - '0');}ret *= sgn;return 1;}inline bool scan_lf(double &num){char in;double Dec=0.1;bool IsN=false,IsD=false;in=getchar();if(in==EOF) return false;while(in!='-'&&in!='.'&&(in<'0'||in>'9'))in=getchar();if(in=='-'){IsN=true;num=0;}else if(in=='.'){IsD=true;num=0;}else num=in-'0';if(!IsD){while(in=getchar(),in>='0'&&in<='9'){num*=10;num+=in-'0';}}if(in!='.'){if(IsN) num=-num;return true;}else{while(in=getchar(),in>='0'&&in<='9'){num+=Dec*(in-'0');Dec*=0.1;}}if(IsN) num=-num;return true;}void Out(LL a){if(a < 0) { putchar('-'); a = -a; }if(a >= 10) Out(a / 10);putchar(a % 10 + '0');}void print(LL a){ Out(a),puts("");}//freopen( "in.txt" , "r" , stdin );//freopen( "data.txt" , "w" , stdout );//cerr << "run time is " << clock() << endl;//http://www.cnblogs.com/phile/p/6391465.htmlLL n,m,p;LL Fc[maxn][maxn];LL Fcx[maxn][maxn];void f(LL x,LL y){    LL tx=x,ty=y;    LL c=0;    while(y>0)    {        c+=1;        LL t=x%y;        x=y;        y=t;    }    Fc[tx][ty]=c;    Fcx[tx][ty]=c*x*x;}void init(){    for(LL j=1; j<=666; j++)    {        for(LL i=0; i<=j; i++)        {            f(i,j);        }    }}void solve(){    scanf("%I64d%I64d%I64d",&n,&m,&p);    LL ans=0;    FOR(1,m,j)    {        for(int i=1;i<=j&&i<=n;i++)        {            for(int k=0;k<Fc[i][j];k++)            {                if(i+k*j>n) break;                LL b=(i+j*k)*j/Fcx[i][j];                LL d=Fc[i][j]*j*j/Fcx[i][j];                LL t=(n-(i+j*k))/(Fc[i][j]*j)+1;//倍数                ans=(ans+b*t%p+(t-1)*t/2%p*d%p)%p;            }        }    }    print(ans);}int main(){    init();    int t;    scan_d(t);    W(t--)    {        solve();    }}