работа с буфером

histogram.cpp

@@ -0,0 +1,40 @@
+#include "histogram.h"
+bool
+find_minmax(std::vector<double> numbers, double& min, double& max) {
+    if(numbers.size() == 0){
+        return false;
+    }
+    min = numbers[0];
+    max = numbers[0];
+    for (double x : numbers) {
+        if (x < min) {
+            min = x;
+        }
+        else if (x > max)
+        {
+                max = x;
+        }
+    }
+    return true;
+}
+std::vector<size_t>
+make_histogram(const std::vector<double>& numbers,size_t bin_count){
+    std::vector<size_t> bins(bin_count);
+    double min,max;
+    find_minmax(numbers,min,max);
+    double bin_size=(max-min)/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;
+}

histogram.h

@@ -0,0 +1,8 @@
+#ifndef HISTOGRAM_H_INCLUDED
+#define HISTOGRAM_H_INCLUDED
+#include <vector>
+#include <iostream>
+std::vector<size_t>
+make_histogram(const std::vector<double>& numbers, size_t bin_count);
+
+#endif

histogram_internal.h

@@ -0,0 +1,8 @@
+#ifndef HISTOGRAM_INTERNAL_H_INCLUDED
+#define HISTOGRAM_INTERNAL_H_INCLUDED
+#include <vector>
+#include <iostream>
+bool
+find_minmax(const std::vector<double>& numbers, double& min, double& max);
+
+#endif

main.cpp

@@ -1,5 +1,12 @@
+#include <curl/curl.h>
+#include <sstream>
+#include <string>
+#include "histogram.h"
+#include "text.h"
 #include <iostream>
 #include <vector>
+#include "svg.h"
+
 
 using namespace std;
 struct Input {
@@ -7,108 +14,57 @@ struct Input {
     size_t bin_count{};
 };
 Input
-input_data(){
+input_data(istream& in,bool promt = false) {
     size_t number_count;
+    if (promt)
         cerr << "Number_count: ";
-    cin >> number_count;
+    in >> number_count;
-    Input in;
+    Input im;
-    in.numbers.resize(number_count);
+    im.numbers.resize(number_count);
     for (size_t i = 0; i < number_count; i++) {
-        cin >> in.numbers[i];
+        in >> im.numbers[i];
     }
+    if (promt)
         cerr << "Enter bin_count: ";
-    cin >> in.bin_count;
+    in >> im.bin_count;
-    return in;
+    return im;
 }
-void
+size_t write_data(void* items, size_t item_size, size_t item_count, void* ctx){
-find_minmax(const vector<double>& numbers, double& min, double& max) {
+    stringstream* buffer = reinterpret_cast<stringstream*>(ctx);
-    min = numbers[0];
+    size_t data_size = item_size * item_count;
-    max = numbers[0];
+    buffer->write(reinterpret_cast<const char*>(items), data_size);
-    for(double x : numbers){
+    return data_size;
-        if(x<min){
-            min=x;
 }
-        if(x>max){
-            max=x;
-        }
-    }
-}
-vector<size_t>
-make_histogram(const vector<double>& numbers,size_t bin_count){
-    vector<size_t> bins(bin_count);
-    double min,max;
-    find_minmax(numbers,min,max);
-    double bin_size=(max-min)/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;
-}
-void
-show_histogram(vector<size_t>bins,size_t bin_count){
-    size_t Maxbins = 0;
-    for (size_t i = 0; i < bin_count; i++)
-    {
-        if (bins[i] > Maxbins)
-        {
-            Maxbins = bins[i];
-        }
-    }
-    const size_t MAX_HEIGHT = 76;
-    if (Maxbins <= MAX_HEIGHT)
-    {
-        for (size_t i = 0; i < bin_count; i++)
-        {
-            if (bins[i] < 10)
-            {
-                cout << " ";
-            }
-            cout << " " << bins[i]<< "|";
-            for (size_t j = 0; j < bins[i]; j++)
-            {
-                cout << "*";
-            }
-            cout << endl;
-        }
-    }
-    else
-    {
-        for (size_t i = 0; i < bin_count; i++)
-        {
-            size_t height = static_cast<size_t>(MAX_HEIGHT * (static_cast<double>(bins[i]) / Maxbins));
 
-            if (bins[i] < 100)
+Input download(const string& address) {
-            {
+    stringstream buffer;
-                cout << " ";
+    CURL *curl = curl_easy_init();
-            }
+    if(curl) {
-            if (bins[i] < 10)
+        curl_easy_setopt(curl, CURLOPT_URL, address.c_str());
-            {
+        curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, write_data);
-                cout << " ";
+        curl_easy_setopt(curl, CURLOPT_WRITEDATA, &buffer);
-            }
+        CURLcode res = curl_easy_perform(curl);
-            cout << bins[i] << "|";
+        curl_easy_cleanup(curl);
-            for (size_t j = 0; j < height; j++)
+        if(res != 0){
-            {
+            cerr << curl_easy_strerror(res);
-                cout << "*";
+            exit(1);
-            }
-            cout << endl;
         }
     }
+    return input_data(buffer, false);
 }
-int
+
-main() {
+int main(int argc, char* argv[]) {
-    auto in = input_data();
+
-    auto bins = make_histogram(in.numbers, in.bin_count);
+    curl_global_init(CURL_GLOBAL_ALL);
-    show_histogram(bins,in.bin_count);
+
+    Input input;
+    if (argc > 1) {
+        input = download(argv[1]);
+    } else {
+        input = input_data(cin, true);
+    }
+    auto bins = make_histogram(input.numbers, input.bin_count);
+    show_histogram_svg(bins);
     return 0;
 }
 

svg.cpp

@@ -0,0 +1,48 @@
+#include "svg.h"
+void
+svg_begin(double width, double height) {
+    std::cout << "<?xml version='1.0' encoding='UTF-8'?>\n";
+    std::cout << "<svg ";
+    std::cout << "width='" << width << "' ";
+    std::cout << "height='" << height << "' ";
+    std::cout << "viewBox='0 0 " << width << " " << height << "' ";
+    std::cout << "xmlns='http://www.w3.org/2000/svg'>\n";
+}
+
+void
+svg_end() {
+    std::cout << "</svg>\n";
+}
+void
+svg_text(double left, double baseline, std::string text) {
+    std::cout << "<text x='" << left << "' y='" << baseline << "'>" << text << "</text>";
+}
+void
+svg_rect(double x,double y,double width,double height,std::string stroke = "red",std::string fill= "black"){
+    std::cout << "<rect x='"<<x<<"' y='"<<y<<"' width='"<<width<<"' height='"<<height<<"' stroke='"<<stroke<<"' fill='"<<fill<<"' />";}
+void
+show_histogram_svg(const std::vector<size_t>& bins) {
+    const auto IMAGE_WIDTH = 400;
+    const auto IMAGE_HEIGHT = 300;
+    const auto TEXT_LEFT = 20;
+    const auto TEXT_BASELINE = 20;
+    const auto TEXT_WIDTH = 50;
+    const auto BIN_HEIGHT = 30;
+    const auto BLOCK_WIDTH = 10;
+    const auto COLOUR_1 = "green";
+    const auto COLOUR_2 = "blue";
+    svg_begin(400, 300);
+
+    double top = 0;
+    for (size_t bin : bins)
+        {
+        const double bin_width = BLOCK_WIDTH * bin;
+        svg_text(TEXT_LEFT, top + TEXT_BASELINE, std::to_string(bin));
+        svg_rect(TEXT_WIDTH, top, bin_width, BIN_HEIGHT,COLOUR_1,COLOUR_2);
+        top += BIN_HEIGHT;
+    }
+
+    svg_end();
+}
+
+

svg.h

@@ -0,0 +1,8 @@
+#ifndef SVG_H_INCLUDED
+#define SVG_H_INCLUDED
+#include <vector>
+#include <iostream>
+void
+show_histogram_svg(const std::vector<size_t>& bins);
+
+#endif

text.cpp

@@ -0,0 +1,51 @@
+#include "text.h"
+void
+show_histogram_text(std::vector<size_t>bins,size_t bin_count){
+    size_t Maxbins = 0;
+    for (size_t i = 0; i < bin_count; i++)
+    {
+        if (bins[i] > Maxbins)
+        {
+            Maxbins = bins[i];
+        }
+    }
+    const size_t MAX_HEIGHT = 76;
+    if (Maxbins <= MAX_HEIGHT)
+    {
+        for (size_t i = 0; i < bin_count; i++)
+        {
+            if (bins[i] < 10)
+            {
+                std::cout << " ";
+            }
+            std::cout << " " << bins[i]<< "|";
+            for (size_t j = 0; j < bins[i]; j++)
+            {
+                std::cout << "*";
+            }
+            std::cout << std::endl;
+        }
+    }
+    else
+    {
+        for (size_t i = 0; i < bin_count; i++)
+        {
+            size_t height = static_cast<size_t>(MAX_HEIGHT * (static_cast<double>(bins[i]) / Maxbins));
+
+            if (bins[i] < 100)
+            {
+                std::cout << " ";
+            }
+            if (bins[i] < 10)
+            {
+                std::cout << " ";
+            }
+            std::cout << bins[i] << "|";
+            for (size_t j = 0; j < height; j++)
+            {
+                std::cout << "*";
+            }
+            std::cout << std::endl;
+        }
+    }
+}

text.h

@@ -0,0 +1,8 @@
+#ifndef TEXT_H_INCLUDED
+#define TEXT_H_INCLUDED
+#include <vector>
+#include <iostream>
+void
+show_histogram_text(std::vector<size_t>bins,size_t bin_count);
+
+#endif

unittest.cpp

@@ -0,0 +1,38 @@
+#define DOCTEST_CONFIG_NO_MULTITHREADING
+#define DOCTEST_CONFIG_IMPLEMENT_WITH_MAIN
+#include "doctest.h"
+#include "histogram_internal.h"
+
+TEST_CASE("distinct positive numbers") {
+    double min = 0;
+    double max = 0;
+    find_minmax({2, 2}, min, max);
+    CHECK(min == 2);
+    CHECK(max == 2);
+}
+TEST_CASE("empty vector"){
+    double min = 0;
+    double max = 0;
+    CHECK(!find_minmax({}, min, max));
+}
+TEST_CASE("vector of one elements"){
+    double min = 0;
+    double max = 0;
+    find_minmax({3}, min, max);
+    CHECK(min == max);
+}
+TEST_CASE("distinct negative numbers"){
+    double min = 0;
+    double max = 0;
+    find_minmax({-1, -2}, min, max);
+    CHECK(min == -2);
+    CHECK(max == -1);
+}
+TEST_CASE("vector of the same elements"){
+    double min = 0;
+    double max = 0;
+    find_minmax({3,3,3}, min, max);
+    CHECK(min == 3);
+    CHECK(max == 3);
+}
+