In this HackerEarth Divide and distribute problem solution You are given a graph in the form of a matrix of size N * M containing '#' and '.'.All the cells containing '#' are nodes of the graph and two nodes are considered to be connected if they are present at the top, left, right, or bottom of each other. Initially, the graph is connected.

Write a program to determine the minimum number of nodes that need to be deleted from the graph in order to break it into two unconnected graphs.


HackerEarth Divide and distribute problem solution


HackerEarth Divide and distribute problem solution.

#include <bits/stdc++.h>

using namespace std;

#define bug() printf("BUG\n")
#define bug1(n) printf("bg1 %d\n",n)
#define bug2(a,b) printf("bg2 %d %d\n",a,b)
#define MOD 1000000007
#define ll long long
#define vi vector< int >
#define vll vector< long long >
#define vvi vector< vector< int > >
#define vvll vector< vector< long long > >
#define pi pair< int, int >
#define pll pair< long long, long long >
#define vpi vector< pair< int, int > >
#define vpll vector< pair< long long, long long > >
#define pb(n) push_back(n)
#define mp(a,b) make_pair(a,b)
#define printA(a,n) for(int i = 0;i < n;++i) cout<<a[i]<<" "; cout<<endl;

int check5Cond(char s[101][101],int n, int m)
{
for (int i = 0; i < n; ++i)
{
for (int j = 0; j < m; ++j)
{
if(s[i][j] == '#')
{
int temp = 0;
if(j-1 >= 0 && s[i][j-1] == '#')
temp++;
if(j+1 < m && s[i][j+1] == '#')
temp++;
if(i-1 >= 0 && s[i-1][j] == '#')
temp++;
if(i+1 < n && s[i+1][j] == '#')
temp++;
if(temp == 4)
{
return 1;
}
}
}
}
return 0;
}

void printMap(map< pi,int> mymap)
{
map< pi,int >::iterator it = mymap.begin();
for (it=mymap.begin(); it!=mymap.end(); ++it)
cout << it->first.first<<","<< it->first.second << " => " << it->second << '\n';
}

int checkFor(char s[101][101],int n,int m,int x,int y)
{
// printf("\n%d %d\n", x,y);
// printf("BUG1\n");
int tx,ty;
pi p;
stack< pi >st;
map< pi,int >mymap;
mymap[mp(x,y)] = 3;
if(x-1 >= 0 && s[x-1][y] == '#')
{
st.push(mp(x-1,y));
mymap[mp(x-1,y)] = 1;
}
else if(x+1 < n && s[x+1][y] == '#')
{
st.push(mp(x+1,y));
mymap[mp(x+1,y)] = 1;
}
else if(y-1 >= 0 && s[x][y-1] == '#')
{
st.push(mp(x,y-1));
mymap[mp(x,y-1)] = 1;
}
else if(y+1 < m && s[x][y+1] == '#')
{
st.push(mp(x,y+1));
mymap[mp(x,y+1)] = 1;
}
while(!st.empty())
{
p = st.top();
st.pop();
tx = p.first;ty = p.second;
// printf("%d %d\n", tx,ty);
if(!(tx == x && ty == y))
{
mymap[mp(tx,ty)] = 1;
if(tx-1 >= 0 && s[tx-1][ty] == '#' && mymap.find(mp(tx-1,ty)) == mymap.end())
st.push(mp(tx-1,ty));
if(tx+1 < n && s[tx+1][ty] == '#' && mymap.find(mp(tx+1,ty)) == mymap.end())
st.push(mp(tx+1,ty));
if(ty-1 >= 0 && s[tx][ty-1] == '#' && mymap.find(mp(tx,ty-1)) == mymap.end())
st.push(mp(tx,ty-1));
if(ty+1 < m && s[tx][ty+1] == '#' && mymap.find(mp(tx,ty+1)) == mymap.end())
st.push(mp(tx,ty+1));
}
}
/*
printMap(mymap);
printf("\n");
printf("BUG2\n");
*/
if(x-1 >= 0 && s[x-1][y] == '#' && mymap.find(mp(x-1,y)) == mymap.end())
{
st.push(mp(x-1,y));
mymap[mp(x-1,y)] = 2;
}
else if(x+1 < n && s[x+1][y] == '#' && mymap.find(mp(x+1,y)) == mymap.end())
{
st.push(mp(x+1,y));
mymap[mp(x+1,y)] = 2;
}
else if(y-1 >= 0 && s[x][y-1] == '#' && mymap.find(mp(x,y-1)) == mymap.end())
{
st.push(mp(x,y-1));
mymap[mp(x,y-1)] = 2;
}
else if(y+1 < m && s[x][y+1] == '#' && mymap.find(mp(x,y+1)) == mymap.end())
{
st.push(mp(x,y+1));
mymap[mp(x,y+1)] = 2;
}
int flag = 0;
while(!st.empty())
{
flag = 1;
p = st.top();
st.pop();
tx = p.first;ty = p.second;
// printf("%d %d\n", tx,ty);
if(!(tx == x && ty == y))
{
mymap[mp(tx,ty)] = 2;
if(tx-1 >= 0 && s[tx-1][ty] == '#' && mymap.find(mp(tx-1,ty)) == mymap.end())
st.push(mp(tx-1,ty));
if(tx+1 < n && s[tx+1][ty] == '#' && mymap.find(mp(tx+1,ty)) == mymap.end())
st.push(mp(tx+1,ty));
if(ty-1 >= 0 && s[tx][ty-1] == '#' && mymap.find(mp(tx,ty-1)) == mymap.end())
st.push(mp(tx,ty-1));
if(ty+1 < m && s[tx][ty+1] == '#' && mymap.find(mp(tx,ty+1)) == mymap.end())
st.push(mp(tx,ty+1));
}
}
if(flag == 0)
return 0;
// printMap(mymap);
for (int i = 0; i < n; ++i)
{
for (int j = 0; j < m; ++j)
{
// if(s[i][j] == '#')
// printf("%d %d\n%d\n",i,j, mymap[mp(i,j)]);
if(s[i][j] == '#' /*&& mymap.find(mp(i,j)) == mymap.end()*/ && mymap[mp(i,j)] == 0)
return 0;
}
}
return 1;
}

int main()
{
int t;
scanf("%d",&t);
while(t--)
{
int n,m;
scanf("%d %d",&n,&m);
char s[101][101],ts[101][101];
int cnt = 0;
getchar();
for (int i = 0; i < n; ++i)
{
for (int j = 0; j < m; ++j)
{
s[i][j] = getchar();
ts[i][j] = s[i][j];
if(s[i][j] == '#')
cnt++;
}
getchar();
}

if (cnt < 3)
{
printf("-1\n");
continue;
}

if(cnt == 5 && check5Cond(s,n,m))
{
printf("3\n");
continue;
}

int temp,flag = 0;
for (int i = 0; i < n; ++i)
{
for (int j = 0; j < m; ++j)
{
temp = 0;
if(j-1 >= 0 && s[i][j-1] == '#')
temp++;
if(j+1 < m && s[i][j+1] == '#')
temp++;
if(i-1 >= 0 && s[i-1][j] == '#')
temp++;
if(i+1 < n && s[i+1][j] == '#')
temp++;
if(temp == 1)
{
continue;
}
if(temp == 4)
{
if(j-1 >= 0 && i-1 >= 0 && s[i-1][j-1] == '#')
temp++;
if(j-1 >= 0 && i+1 < n && s[i+1][j-1] == '#')
temp++;
if(j+1 < m && i-1 >= 0 && s[i-1][j+1] == '#')
temp++;
if(j+1 > m && i+1 < n && s[i+1][j+1] == '#')
temp++;
if(temp > 6)
continue;
}
if(s[i][j] == '#' && checkFor(s,n,m,i,j))
{
flag = 1;
goto endLoop;
}
}
}

endLoop:
{
if(flag == 1)
printf("1\n");
else
printf("2\n");
}

}
return 0;
}