CSU 1469: Handles 1484: Central Avenue Road 1497: The Gougu Theorem

1469: Handles

#include <stdio.h>
#include <string.h>
using namespace std;
char a[1005][1005];
int xx[1005],yy[1005];
int n,m;
int main()
{
    int t;
    scanf("%d",&t);
    while(t--)
    {
        scanf("%d%d",&n,&m);
        memset(xx,0,sizeof(xx));
        memset(yy,0,sizeof(yy));
        for(int i=0;i<n;i++)
            scanf("%s",a[i]);
        int q;
        scanf("%d",&q);
        while(q--)
        {
            int x,y;
            scanf("%d%d",&x,&y);
            a[x-1][y-1]=(a[x-1][y-1]=='+'?'-':'+');
            xx[x-1]++;
            yy[y-1]++;
        }
        for(int i=0;i<n;i++)
        {
                if(xx[i]%2!=0)
                    {
                        for(int j=0;j<m;j++)
                            a[i][j]=(a[i][j]=='+'?'-':'+');
                    }
        }
        for(int i=0;i<m;i++)
        {
                if(yy[i]%2!=0)
                    {
                        for(int j=0;j<n;j++)
                            a[j][i]=(a[j][i]=='+'?'-':'+');
                    }
        }
        int sum=0;
        for(int i=0;i<n;i++)
            for(int j=0;j<m;j++)
                if(a[i][j]=='+')
                    sum++;
        printf("%d\n",sum);
    }
    return 0;
}


/**********************************************************************
	Problem: 1469
	User: 3901140225
	Language: C++
	Result: AC
	Time:292 ms
	Memory:2112 kb
**********************************************************************/

1484: Central Avenue Road

#include <iostream>
#include<cstdio>
#include<cmath>
#include<cstring>
using namespace std;
const int maxn=105;
int x[maxn],y[maxn];
int n;
double dist(int i,int j)
{
    return  sqrt((x[i]-x[j])*(x[i]-x[j])+(y[i]-y[j])*(y[i]-y[j])+0.000001);
}
bool judge(int i,int j)
{

    int a=y[j]-y[i];
    int b=x[i]-x[j];
    int c=x[j]*y[i]-x[i]*y[j];
    int u=x[i]-x[j];
    int d=y[i]-y[j];
    int lf=0,rt=0;
    if(u==0&&d!=0)
    {
        for(int k=0; k<n; k++)
        {
            if(x[k]<x[i])
            {
                lf++;
            }
            if(x[k]>x[i])
            {
                rt++;
            }
        }
    }
    else if(d==0&&u!=0)
    {
        for(int k=0; k<n; k++)
        {
            if(y[k]<y[i])
            {
                lf++;
            }
            if(y[k]>y[i])
            {
                rt++;
            }
        }
    }
    else
    {
        for(int k=0; k<n; k++)
        {
            if(a*x[k]+b*y[k]+c>0)
            {
                lf++;
            }
            else if(a*x[k]+b*y[k]+c<0)
            {
                rt++;
            }
        }
    }
    if(fabs(rt-lf)<=1) return true;
    else return false;
}
int main()
{
    while(~scanf("%d",&n)&&n)
    {
        for(int i=0; i<n; i++)
        {
            scanf("%d%d",&x[i],&y[i]);
        }
        double Max=0x3f3f3f3f3f;
        for(int i=0;i<n;i++){
            for(int j=i+1;j<n;j++){
                if(judge(i,j)){
                    double temp=dist(i,j);
                    if(temp<Max)
                        Max=temp;
                }
            }
        }
        printf("%.3lf\n",Max);
    }
    return 0;
}


/**********************************************************************
	Problem: 1484
	User: 3901140225
	Language: C++
	Result: AC
	Time:108 ms
	Memory:2036 kb
**********************************************************************/

1497: The Gougu Theorem

#include<iostream>
#include<algorithm>
using namespace std;
#include<map>
const int MOD=1e9+7;
typedef long long ll;
map<pair<ll,ll>,int>v;
map<pair<ll,ll>,int>::iterator it;
int gcd(ll x,ll y){return y==0?x:gcd(y,x%y);}
int main()
{
    ll c;
    int cas=0;
    while(scanf("%lld",&c)!=EOF&&c)
    {
        v.clear();
        ll m=sqrt(c);
        for(ll i=1;i<=m;i++)
        {
            ll j=sqrt(c-i*i);
            if(j*j+i*i!=c||j<=i)continue;
            ll x=j*j-i*i;
            ll y=2*j*i;
            if(x>y)swap(x,y);
            if(gcd(x,y)!=1||gcd(x,c)!=1||gcd(c,y)!=1)continue;
            if(v[make_pair(x,y)])continue;
            v[make_pair(x,y)]=1;
        }
        if(cas)printf("\n");
        printf("Case %d:\n",++cas);
        printf("There are %d solution(s).\n",v.size());
        for(it=v.begin();it!=v.end();it++)printf("%lld^2 + %lld^2 = %lld^2\n",it->first.first,it->first.second,c);
    }
    return 0;
}