SIGSEGV in Spoj GSS1

Hi,

I have been trying to solve GSS1 on Spoj and its giving me segmentation fault. I am not able to figure out whats the problem. Below is my code, please see if you can figure out whats the problem.

``````#include <iostream>
#include <algorithm>
#define MAX 500005
using namespace std;

struct data {
long long sum, prefix_sum, suffix_sum, ans;
data(long long val) {
sum = val;
prefix_sum = suffix_sum = ans = max(0LL, val);
}
data(long long a, long long b, long long c, long long d) : sum(a), prefix_sum(b), suffix_sum(c), ans(d) {}
data(){}
};

data tree[4 * MAX];
long long arr[MAX];

data combine(data l, data r)
{
data res;
res.sum = l.sum + r.sum;
res.prefix_sum = max(l.prefix_sum, l.sum + r.prefix_sum);
res.suffix_sum = max(r.suffix_sum, r.sum + l.suffix_sum);
res.ans = max(max(l.ans, r.ans), l.suffix_sum + r.prefix_sum);

return res;
}

void build(long long node, long long tl, long long tr)
{
if (tl > tr) return;

if (tl == tr)
tree[node] = data(arr[tl]);
else {
long long tm = (tl + tr) / 2;
build(node * 2, tl, tm);
build((node * 2) + 1, tm + 1, tr);

tree[node] = combine(tree[node * 2], tree[(node * 2) + 1]);
}
}

data query(long long node, long long tl, long long tr, long long l, long long r)
{
if (tl > tr || r < tl || l > tr) return data(0, -1e9, -1e9, -1e9);

if (tl <= l && r >= tr)
return tree[node];

long long tm = (tl + tr) / 2;
data n1 = query(node * 2, tl, tm, l, r);
data n2 = query((node * 2) + 1, tm + 1, tr, l, r);

return combine(n1, n2);
}

int main()
{
ios::sync_with_stdio(false);
cin.tie(0);

long long n;
cin >> n;
for (long long i = 0; i < n; i++)
cin >> arr[i];

build(1, 0, n - 1);
long long m;
cin >> m;
while (m--) {
long long x, y;
cin >> x >> y;
cout << query(1, 0, n - 1, x - 1, y - 1).ans << "\n";
}

return 0;
}
``````

PS: Got AC.!! (tl <= l && r >= tr) should be (tl >= l && tr <= r)

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