hdu-multi-university contest 4

#include <iostream>
#include "stdio.h"
#include "stdlib.h"
#include "string.h"
#include "math.h"
#include <algorithm>
using namespace std;
int answer[100002]={0};
int judge(int x)
{
int as[7],pos=0;
while(x)
{
as[pos++]=x%10;
x/=10;
}
if(pos==1) return 1;
for(int i=0;i<pos;i++)
for(int j=i+1;j<pos;j++)
if(as[i]==as[j])  return 0;
return 1;
}
int main()
{
int t,a,b;
scanf("%d",&t);
for(int i=1;i<=100000;i++)
if(judge(i)) answer[i]=answer[i-1]+1;
else answer[i]=answer[i-1];
while(t--)
{
scanf("%d%d",&a,&b);
printf("%d\n",answer[b]-answer[a-1]);
}
return 0;
/*
int a,b;
while(scanf("%d",&a)!=EOF)
{
if(judge(a)) printf("yes\n");
else printf("NO\n");
}*/
}

求序列中最长的数列长度（等比或者等差）
#include <iostream>
#include "stdio.h"
#include "stdlib.h"
#include "string.h"
#include "math.h"
#include <algorithm>
using namespace std;

long long int ss[1000005];
int main(void)
{
int t,maxn,n,ans;
scanf("%d",&t);
while(t--)
{
maxn=2;
scanf("%d",&n);
for(int i=1;i<=n;i++)
scanf("%d",&ss[i]);
if(n<=2) {
printf("%d\n",n);
continue;
}
ans=2;
for(int i=3;i<=n;i++)
{
if(ss[i-2]+ss[i]==ss[i-1]*2) ans++;
else ans=2;
maxn=max(ans,maxn);
}
ans=2;
for(int i=3;i<=n;i++)
{
if(ss[i-2]*ss[i]==ss[i-1]*ss[i-1])  ans++;
else ans=2;
maxn=max(ans,maxn);
}
printf("%d\n",maxn);
}
}

#include <iostream>
#include "stdio.h"
#include "stdlib.h"
#include "string.h"
#include "math.h"
#include <algorithm>
using namespace std;
#define N 1002
char ss[N][N];
int vis[N][N],que[N];
int n,m,sx,sy,leap,flag;
int dir[4][2]={1,0,0,1,-1,0,0,-1};
int isin(int x,int y)
{
return x>=0&&x<n&&y>=0&&y<m;
}
void bfs(int x,int y)
{
int pre,last,tempx,tempy;
pre=last=0;
memset(que,0,sizeof que);
que[last++]=x;
que[last++]=y;
while(pre<last)
{
tempx=que[pre++];
tempy=que[pre++];
for(int i=0;i<4;i++)
{
int nx=tempx+dir[i][0];
int ny=tempy+dir[i][1];
if(!isin(nx,ny)||vis[nx][ny])  continue;
vis[nx][ny]=1;
if(ss[nx][ny]=='0'){
que[last++]=nx;
que[last++]=ny;
}
if(nx+ny>sx+sy){
sx=nx;
sy=ny;
}
}
}
}
int main()
{
int t;
scanf("%d",&t);
while(t--)
{
memset(vis,0,sizeof(vis));
scanf("%d%d",&n,&m);
for(int i=0;i<n;i++)
scanf("%s",ss[i]);
sx=sy=0;
vis[0][0]=1;
if(ss[0][0]=='0') bfs(0,0);
if(ss[sx][sy]=='0')  printf("0\n");
else {
leap=0;
printf("1");
for(int i=sx+sy;i<n+m-2;i++)
{
flag=0;
for(int k=0;k<=i;k++)
{
int nx=k;
int ny=i-k;
if(!isin(nx,ny)||!vis[nx][ny]) continue;
if(leap&&ss[nx][ny]=='1') continue;
for(int j=0;j<2;j++)
{
int x=nx+dir[j][0];
int y=ny+dir[j][1];
if(!isin(x,y)) continue;
vis[x][y]=1;
if(ss[x][y]=='0') flag=1;
}
}
leap=flag;
printf("%c",flag?'0':'1');
}
printf("\n");
}

}
}