diff --git a/cpp/histogram.hpp b/cpp/histogram.hpp
new file mode 100644
index 0000000000000000000000000000000000000000..f6e6a02c6a2879d7452f7e60ce601f5c16a6e91c
--- /dev/null
+++ b/cpp/histogram.hpp
@@ -0,0 +1,50 @@
+#pragma once
+#include "exports.hpp"
+#include <algorithm>
+#include <vector>
+
+// Histogram over integers with binsize 1
+class Histogram {
+  public:
+    Histogram() : xmin(0) {}
+    ~Histogram() {}
+
+    void reset() {
+        frequencies.clear();
+        xmin = 0;
+    }
+
+    void add(int sample) {
+        if (frequencies.empty()) {
+            xmin = sample;
+            frequencies.push_back(1);
+            return;
+        }
+        if (sample < xmin) {
+            int extra = xmin - sample;
+            frequencies.insert(frequencies.begin(), extra, 0);
+            xmin = sample;
+            frequencies.front()++;
+            return;
+        }
+        if (sample - xmin >= (int)frequencies.size()) {
+            int extra = sample - xmin - frequencies.size() + 1;
+            frequencies.insert(frequencies.end(), extra, 0);
+            frequencies.back()++;
+            return;
+        }
+        frequencies[sample - xmin]++;
+    }
+
+    // For exports
+    std::vector<std::pair<int, int>> getHistogram() const {
+        std::vector<std::pair<int, int>> histogram;
+        int i = xmin;
+        for (auto f : frequencies)
+            histogram.push_back({i++, f});
+        return histogram;
+    }
+
+    std::vector<int> frequencies;
+    int xmin;
+};