From 3e68bbbef52e859a80af7f068e1477c0433fe35f Mon Sep 17 00:00:00 2001
From: Stephen Seo <seo.disparate@gmail.com>
Date: Fri, 5 Jun 2020 23:26:14 +0900
Subject: [PATCH] Impl working solution

---
 src/main.c | 115 +++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 115 insertions(+)

diff --git a/src/main.c b/src/main.c
index 11b7fad..00503a4 100644
--- a/src/main.c
+++ b/src/main.c
@@ -1,3 +1,118 @@
+#include <string.h>
+#include <stdlib.h>
+#include <stdio.h>
+
+typedef struct SimpleVector {
+    int *data;
+    unsigned int capacity;
+    unsigned int size;
+} SimpleVector;
+
+void sv_init(SimpleVector *sv, unsigned int capacity) {
+    if(!sv->data) {
+        sv->data = (int*)malloc(capacity * sizeof(int));
+        sv->capacity = capacity;
+        sv->size = 0;
+    }
+}
+
+void sv_cleanup(SimpleVector *sv) {
+    if(sv->data) {
+        free(sv->data);
+        sv->data = NULL;
+        sv->capacity = 0;
+        sv->size = 0;
+    }
+}
+
+void sv_add(SimpleVector *sv, int value) {
+    if(!sv->data || sv->capacity == 0) {
+        return;
+    }
+    if(sv->size == sv->capacity) {
+        int *new_data = (int*)malloc(sv->capacity * 2 * sizeof(int));
+        memcpy(new_data, sv->data, sv->size * sizeof(int));
+        free(sv->data);
+        sv->data = new_data;
+        sv->capacity *= 2;
+    }
+
+    sv->data[sv->size] = value;
+    ++sv->size;
+}
+
+void sv_print(SimpleVector *sv) {
+    if(!sv->data || sv->capacity == 0) {
+        puts("Invalid SimpleVector, cannot print");
+        return;
+    } else if(sv->size == 0) {
+        puts("SimpleVector is empty");
+        return;
+    }
+
+    for(unsigned int i = 0; i < sv->size; ++i) {
+        printf("%d ", sv->data[i]);
+    }
+    printf("\n");
+}
+
+int is_digit_sum_equal(int a, int b) {
+    int sum_a = 0;
+    int sum_b = 0;
+
+    while(a > 0) {
+        sum_a += a % 10;
+        a /= 10;
+    }
+    while(b > 0) {
+        sum_b += b % 10;
+        b /= 10;
+    }
+
+    return sum_a == sum_b ? 1 : 0;
+}
+
 int main(int argc, char **argv) {
+    SimpleVector sv;
+    memset(&sv, 0, sizeof(SimpleVector));
+    sv_init(&sv, 32);
+
+    int temp_i;
+    const char *temp_c;
+    --argc; ++argv;
+    while(argc > 0) {
+        temp_i = 0;
+        temp_c = argv[0];
+        while(*temp_c != 0) {
+            if(*temp_c < '0' || *temp_c > '9') {
+                printf("ERROR: Input is not a digit!\n");
+                return 1;
+            }
+            temp_i = temp_i * 10 + *temp_c - '0';
+            ++temp_c;
+        }
+        sv_add(&sv, temp_i);
+        --argc; ++argv;
+    }
+    sv_print(&sv);
+
+    // Actually do the problem here
+    temp_i = 0;
+    int temp_sum;
+    for(unsigned int i = 0; i < sv.size; ++i) {
+        for(unsigned int j = i + 1; j < sv.size; ++j) {
+            if(is_digit_sum_equal(sv.data[i], sv.data[j])) {
+                temp_sum = sv.data[i] + sv.data[j];
+                printf("%d and %d has sum of %d\n", sv.data[i], sv.data[j], temp_sum);
+                if(temp_sum > temp_i) {
+                    temp_i = temp_sum;
+                }
+            }
+        }
+    }
+
+    printf("Got result %d\n", temp_i);
+
+    sv_cleanup(&sv);
     return 0;
 }