# wrong answer in RACELANE

I have tried all test cases i could think of but i am not able to find why it is giving wrong answer.please help.

``````#include<iostream>
using namespace std;
int main()
{
int t,b,i,k;
cin>>t;
while(t--)
{
int len=0;
int q[10][2];
int r[501];
for(i=0;i<501;i++)
r[i]=0;
for(i=0;i<10;i++)
for(int j=0;j<2;j++)
q[i][j]=0;
cin>>b;
int s,e,l;
for(i=0;i<b;i++)
{
cin>>s>>e>>l;
q[l][0]=s;
q[l][1]=e;
}
for(i=0;i<9;i++)
{
if(q[i][0]==0 && q[i+1][0]==0)
continue;
if(q[i][1]>=q[i+1][0] && q[i][1]<=q[i+1][1] && q[i][0]<q[i+1][0])
{
for(k=q[i+1][0];k<=q[i][1];k++)
if(r[k]==0)
{
len++;
r[k]=1;
}
}
else if(q[i+1][0]>=q[i][0] && q[i+1][0]<=q[i][1] && q[i+1][1]>q[i][1])
{
for(k=q[i][1];k<=q[i+1][0];k++)
if(r[k]==0)
{
len++;
r[k]=1;
}
}
else if(q[i][0]<=q[i+1][0] && q[i][1]>=q[i+1][1])
{
for(k=q[i+1][0];k<=q[i+1][1];k++)
if(r[k]==0)
{
len++;
r[k]=1;
}
}
else if(q[i][0]>=q[i+1][0] && q[i][1]<=q[i+1][1])
{
for(k=q[i][0];k<=q[i][1];k++)
if(r[k]==0)
{
len++;
r[k]=1;
}
}
}
cout<<500-len<<endl;
}
return 0;
}``````