Added knapsack 0/1 function

src/algorithms/dynamic_programming/knapsack.h

@@ -0,0 +1,39 @@
+#ifndef KNAPSACK_H
+#define KNAPSACK_H
+
+#ifdef __cplusplus
+#include <iostream>
+#include <vector>
+#include <utility>
+#endif
+
+/**
+* @brief knapsack 0/1 function
+* @param v the passed vector
+* @param capacity the capacity of the knapsack
+* @return int: the maximum value you can collect with a knapsack of the passed capacity
+*/
+int knapsack(std::vector<std::pair<int, int> > &v, int capacity) {
+    if(capacity == 0) {
+        return 0;
+    }
+
+    int n = int(v.size());
+    std::vector<std::vector<int > > dp(n + 1, std::vector<int>(capacity + 1));
+
+    for(int i = 1; i<=n; i++) {
+        for(int j = 0; j<=capacity; j++) {
+            dp[i][j] = dp[i - 1][j];
+            if(i == 0 || j == 0) {
+                dp[i][j] = 0;
+            }
+            else if(v[i - 1].first <= j) {
+                dp[i][j] = std::max(dp[i - 1][j], v[i - 1].second + dp[i - 1][j - v[i - 1].first]);
+            }
+        }
+    }
+
+    return dp[n][capacity];
+}
+
+#endif

tests/algorithms/dynamic_programming/knapsack.cc

@@ -0,0 +1,12 @@
+#include "../../../third_party/catch.hpp"
+#include "../../../src/algorithms/dynamic_programming/knapsack.h"
+
+TEST_CASE("Testing knapsack 0/1 [1]") {
+    std::vector<std::pair<int, int> > v = {{10, 60}, {20, 100}, {30, 120}};
+
+    REQUIRE(knapsack(v, 50) == 220);
+    v.clear();
+    v = {{5, 40}, {3, 20}, {6, 10}, {3, 30}};
+
+    REQUIRE(knapsack(v, 10) == 70);
+}