diff --git a/Number Theory/Segmented Sieve.cpp b/Number Theory/Segmented Sieve.cpp
new file mode 100644
index 0000000..8ac44bc
--- /dev/null
+++ b/Number Theory/Segmented Sieve.cpp	
@@ -0,0 +1,54 @@
+#include <bits/stdc++.h>
+using namespace std;
+
+vector<int> generatePrimesUpTo(int limit) {
+    vector<bool> isPrime(limit + 1, true);
+    isPrime[0] = isPrime[1] = false;
+    for (int p = 2; p * p <= limit; ++p) {
+        if (isPrime[p]) {
+            for (int i = p * p; i <= limit; i += p) {
+                isPrime[i] = false;
+            }
+        }
+    }
+    vector<int> primes;
+    for (int p = 2; p <= limit; ++p) {
+        if (isPrime[p]) {
+            primes.push_back(p);
+        }
+    }
+    return primes;
+}
+void segmentedSieve(int m, int n) {
+    if (m == 1) {
+        m++;
+    }
+    int limit = sqrt(n);
+    vector<int> primes = generatePrimesUpTo(limit);
+    vector<bool> isPrime(n - m + 1, true);
+    for (int p : primes) {
+        int start = max(p * p, m + ((p - m % p) % p));
+        for (int j = start; j <= n; j += p) {
+            isPrime[j - m] = false;
+        }
+    }
+    for (int i = m; i <= n; ++i) {
+        if (isPrime[i - m]) {
+            cout << i << endl;
+        }
+    }
+}
+
+int main() {
+    int t;
+    cin >> t;
+    while (t--) {
+        int m, n;
+        cin >> m >> n;
+        segmentedSieve(m, n);
+        if (t > 0) cout << endl;
+    }
+    return 0;
+}
+
+// https://www.spoj.com/problems/PRIME1/