diff --git a/histogram.cpp b/histogram.cpp
index 3524762..f0585d7 100644
--- a/histogram.cpp
+++ b/histogram.cpp
@@ -1 +1,38 @@
+
 #include "histogram.h"
+#include <vector>
+
+static void find_minmax(const std::vector <double> &numbers, double &min, double &max){
+    min = numbers[0];
+    max = numbers[0];
+    for ( double x : numbers ){
+        if ( x < min ){
+            min = x;
+        } else if ( x > max ){
+            max = x;
+        }
+    }
+}
+
+std::vector<std::size_t> make_histogram(const std::vector<double> &numbers, size_t bin_count) {
+    double min = numbers[0];
+    double max = numbers[0];
+    find_minmax(numbers, min, max);
+    double bin_size = ( max - min ) / bin_count;
+    std::vector<std::size_t> bins ( bin_count );
+    for (size_t i=0; i <  numbers.size(); i++ ){
+        bool found = false;
+        for (size_t j = 0; ( j < bin_count - 1 ) && !found; j++ ){
+            auto lo = min + j * bin_size;
+            auto hi = min + ( j + 1 ) * bin_size;
+            if (lo <= numbers[i] && ( numbers[i] < hi )){
+                bins[j]++;
+                found = true;
+            }
+        }
+        if ( !found ){
+            bins[bin_count-1]++;
+        }
+    }
+    return bins;
+}
diff --git a/main.cpp b/main.cpp
index e76f6b0..8742654 100644
--- a/main.cpp
+++ b/main.cpp
@@ -1,5 +1,6 @@
 #include <iostream>
 #include <vector>
+#include "histogram.h"
 
 using namespace std;