# Light OJ: 1207 – Posters for Election

0

Problem Link : http://www.lightoj.com/volume_showproblem.php?problem=1207

```
/*
If opportunity doesn't knock, build a door.

+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|S|.|S|.|R|.|A|.|S|.|A|.|M|.|K|
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

Success is how high you bounce when you hit bottom.
*/

#include <bits/stdc++.h>

#define pii              pair <int,int>
#define pll              pair <long long,long long>
#define sc               scanf
#define pf               printf
#define Pi               2*acos(0.0)
#define ms(a,b)          memset(a, b, sizeof(a))
#define pb(a)            push_back(a)
#define MP               make_pair
#define db               double
#define ll               long long
#define EPS              10E-10
#define ff               first
#define ss               second
#define sqr(x)           (x)*(x)
#define D(x)             cout<<#x " = "<<(x)<<endl
#define VI               vector <int>
#define DBG              pf("Hi\n")
#define MOD              1000000007
#define CIN              ios_base::sync_with_stdio(0); cin.tie(0)
#define SZ(a)            (int)a.size()
#define sf(a)            scanf("%d",&a)
#define sfl(a)           scanf("%lld",&a)
#define sff(a,b)         scanf("%d %d",&a,&b)
#define sffl(a,b)        scanf("%lld %lld",&a,&b)
#define sfff(a,b,c)      scanf("%d %d %d",&a,&b,&c)
#define sfffl(a,b,c)     scanf("%lld %lld %lld",&a,&b,&c)
#define stlloop(v)       for(__typeof(v.begin()) it=v.begin();it!=v.end();it++)
#define loop(i,n)        for(int i=0;i<n;i++)
#define REP(i,a,b)       for(int i=a;i<b;i++)
#define RREP(i,a,b)      for(int i=a;i>=b;i--)
#define TEST_CASE(t)     for(int z=1;z<=t;z++)
#define PRINT_CASE       printf("Case %d: ",z)
#define CASE_PRINT       cout<<"Case "<<z<<": "
#define all(a)           a.begin(),a.end()
#define intlim           2147483648
#define infinity         (1<<28)
#define ull              unsigned long long
#define gcd(a, b)        __gcd(a, b)
#define lcm(a, b)        ((a)*((b)/gcd(a,b)))

using namespace std;

/*----------------------Graph Moves----------------*/
//const int fx[]={+1,-1,+0,+0};
//const int fy[]={+0,+0,+1,-1};
//const int fx[]={+0,+0,+1,-1,-1,+1,-1,+1};   // Kings Move
//const int fy[]={-1,+1,+0,+0,+1,+1,-1,-1};  // Kings Move
//const int fx[]={-2, -2, -1, -1,  1,  1,  2,  2};  // Knights Move
//const int fy[]={-1,  1, -2,  2, -2,  2, -1,  1}; // Knights Move
/*------------------------------------------------*/

/*-----------------------Bitmask------------------*/
//int Set(int N,int pos){return N=N | (1<<pos);}
//int reset(int N,int pos){return N= N & ~(1<<pos);}
//bool check(int N,int pos){return (bool)(N & (1<<pos));}
/*------------------------------------------------*/

struct data
{
int sum, prop;
};

data tree[3*200005];

void push_down(int n, int b, int e)
{
if(tree[n].prop!=-1)
{
int mid=(b+e)/2;
tree[n*2].sum=(mid-b+1)*tree[n].prop;
tree[n*2+1].sum=(e-mid)*tree[n].prop;
tree[2*n].prop=tree[n].prop;
tree[2*n+1].prop=tree[n].prop;
tree[n].prop=-1;
}
}

void push_up(int n)
{
tree[n].sum=tree[n*2].sum+tree[n*2+1].sum;
}

void update(int n, int b, int e, int i, int j, int x)
{
if(i>e || j<b) return;
if(b>=i && e<=j)
{
tree[n].sum=x;
tree[n].prop=x;
return;
}

push_down(n,b,e);

int l=n*2;
int r=l+1;
int mid=(b+e)/2;

update(l,b,mid,i,j,x);
update(r,mid+1,e,i,j,x);

push_up(n);

}

bool query(int n, int b, int e, int i, int j)
{
if(i>e || j<b) return 0;
if(b>=i && e<=j) return tree[n].sum;
push_down(n, b, e);
int l=n*2;
int r=l+1;
int mid=(b+e)/2;

int p=query(l,b,mid,i,j);
int q=query(r,mid+1,e,i,j);
push_up(n);
return p|q;
}

int main()
{
///freopen("in.txt","r",stdin);
///freopen("out.txt","w",stdout);

int t;
sf(t);
TEST_CASE(t)
{
vector<pii>v;
int n;
sf(n);

loop(i,n)
{
int a,b;
sff(a,b);
v.pb(MP(a,b));
}
reverse(all(v));

int ans=0;

update(1,1,200000,1,200000,1);

loop(i,n)
{
if(query(1,1,200000,v[i].ff,v[i].ss))
{
ans++;
update(1,1,200000,v[i].ff,v[i].ss,0);
}
}
PRINT_CASE;
printf("%d\n",ans);
}

return 0;
}

```

# Light OJ: 1097 – Lucky Number

0

Problem Link: http://www.lightoj.com/volume_showproblem.php?problem=1097

```

/*
If opportunity doesn't knock, build a door.

+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|S|.|S|.|R|.|A|.|S|.|A|.|M|.|K|
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

Success is how high you bounce when you hit bottom.
*/

#include <bits/stdc++.h>

#define pii              pair <int,int>
#define pll              pair <long long,long long>
#define sc               scanf
#define pf               printf
#define Pi               2*acos(0.0)
#define ms(a,b)          memset(a, b, sizeof(a))
#define pb(a)            push_back(a)
#define MP               make_pair
#define db               double
#define ll               long long
#define EPS              10E-10
#define ff               first
#define ss               second
#define sqr(x)           (x)*(x)
#define D(x)             cout<<#x " = "<<(x)<<endl
#define VI               vector <int>
#define DBG              pf("Hi\n")
#define MOD              1000000007
#define CIN              ios_base::sync_with_stdio(0); cin.tie(0)
#define SZ(a)            (int)a.size()
#define sf(a)            scanf("%d",&a)
#define sfl(a)           scanf("%lld",&a)
#define sff(a,b)         scanf("%d %d",&a,&b)
#define sffl(a,b)        scanf("%lld %lld",&a,&b)
#define sfff(a,b,c)      scanf("%d %d %d",&a,&b,&c)
#define sfffl(a,b,c)     scanf("%lld %lld %lld",&a,&b,&c)
#define stlloop(v)       for(__typeof(v.begin()) it=v.begin();it!=v.end();it++)
#define loop(i,n)        for(int i=0;i<n;i++)
#define REP(i,a,b)       for(int i=a;i<b;i++)
#define RREP(i,a,b)      for(int i=a;i>=b;i--)
#define TEST_CASE(t)     for(int z=1;z<=t;z++)
#define PRINT_CASE       printf("Case %d: ",z)
#define CASE_PRINT       cout<<"Case "<<z<<": "
#define all(a)           a.begin(),a.end()
#define intlim           2147483648
#define infinity         (1<<28)
#define ull              unsigned long long
#define gcd(a, b)        __gcd(a, b)
#define lcm(a, b)        ((a)*((b)/gcd(a,b)))

using namespace std;

/*----------------------Graph Moves----------------*/
//const int fx[]={+1,-1,+0,+0};
//const int fy[]={+0,+0,+1,-1};
//const int fx[]={+0,+0,+1,-1,-1,+1,-1,+1};   // Kings Move
//const int fy[]={-1,+1,+0,+0,+1,+1,-1,-1};  // Kings Move
//const int fx[]={-2, -2, -1, -1,  1,  1,  2,  2};  // Knights Move
//const int fy[]={-1,  1, -2,  2, -2,  2, -1,  1}; // Knights Move
/*------------------------------------------------*/

/*-----------------------Bitmask------------------*/
//int Set(int N,int pos){return N=N | (1<<pos);}
//int reset(int N,int pos){return N= N & ~(1<<pos);}
//bool check(int N,int pos){return (bool)(N & (1<<pos));}
/*------------------------------------------------*/

int mm=1429431;

int tree[1429450*4];

void init(int n,int b, int e)
{
if(b==e)
{
if(b%2==1) tree[n]=1;
else tree[n]=0;
return;
}
int mid=(b+e)/2;
int l=n*2;
int r=l+1;
init(l,b,mid);
init(r,mid+1,e);
tree[n]=tree[l]+tree[r];
}

int query(int n, int b, int e, int x)
{
if(x==1 && b==e) return b;
int l=n*2;
int r=l+1;
int mid=(b+e)/2;
if(x>tree[l]) return query(r,mid+1,e,x-tree[l]);
else
return query(l,b,mid,x);
}

void update(int n, int b, int e, int x)
{
if(x==1 && b==e)
{
tree[n]=0;
return;
}
int l=n*2;
int r=l+1;
int mid=(b+e)/2;
if(x>tree[l]) update(r,mid+1,e,x-tree[l]);
else
update(l,b,mid,x);
tree[n]=tree[l]+tree[r];
}

int main()
{

//    freopen("in.txt","r",stdin);
//    freopen("out.txt","w",stdout);

init(1,1,mm);
for(int i=2; i<=100000; i++)
{
int x=query(1,1,mm,i);
int xx=x;
while(x<tree[1])
{
update(1,1,mm,x);
x+=xx;
x-=1;
}
}

int t;
sf(t);
TEST_CASE(t)
{
int a;
sf(a);
PRINT_CASE;
pf("%d\n",query(1,1,mm,a));
}
return 0;
}

```

# DFS Sample Code

0
```
#include <bits/stdc++.h>

using namespace std;

vector<int>v[100];
bool visited[100];

int node,edge;

void DFS(int n)
{
visited[n]=true;
cout<<n<<" ";
int temp;
for(int i=0; i<v[n].size(); i++)
{
temp=v[n][i];
if(!visited[temp])
DFS(temp);
}
}

int main()
{
cin>>node>>edge;
for(int i=0; i<edge; i++)
{
int x,y;
cin>>x>>y;
v[x].push_back(y);
v[y].push_back(x);
}

int src,dst;
cin>>src>>dst;
memset(visited,0,sizeof visited);
cout<<"DFS traverse order is = ";
DFS(src);
cout<<endl;
if(visited[dst])
cout<<dst<<" is reachable from "<<src<<endl;
else
cout<<dst<<" is not reachable from "<<src<<endl;
return 0;
}

```

# BFS Sample Code

0
```
#include <bits/stdc++.h>

using namespace std;

vector<int>G[100]; // Here 100 is maximum number of Nodes.
bool visited[100];
int parent[100]; // This is used to print path from source to distance
int dis[100];
int node,edge;

void path_print(int u)
{
if(u==-1) return;
path_print(parent[u]);
printf("%d ",u);
}

void bfs(int src)
{
queue<int>Q;
Q.push(src);
dis[src]=0;
parent[src]=-1;
memset(visited,0,sizeof visited);
visited[src]=1 ;

while(!Q.empty())
{
int u=Q.front();
for(int i=0; i<G[u].size(); i++)
{
int v=G[u][i];
if(!visited[v])
{
dis[v]=dis[u]+1 ;
parent[v]=u;
visited[v]=1 ;
Q.push(v);
}
}
Q.pop();
}
for(int i=1 ; i<=node; i++)
{
printf("%d to %d distance = %d\n",src,i,dis[i]);
printf("Path = ");
if(visited[i])
path_print(i);
printf("\n");
}
}

int main()
{
cin>>node>>edge;
for(int i=1; i<=edge; i++)
{
int a,b;
cin>>a>>b;
G[a].push_back(b);
G[b].push_back(a);
}
int src;
cin>>src;
bfs(src);
return 0;
}

```