From 469f204879ea3f0bfc42b5a1937f5fa49f1a2d63 Mon Sep 17 00:00:00 2001
From: Oleksandr Hryshchenko <oh735kh@omega.tuke.sk>
Date: Wed, 10 Mar 2021 00:05:48 +0100
Subject: [PATCH] du3

---
 du3/program.c | 61 +++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 61 insertions(+)
 create mode 100644 du3/program.c

diff --git a/du3/program.c b/du3/program.c
new file mode 100644
index 0000000..903ec9d
--- /dev/null
+++ b/du3/program.c
@@ -0,0 +1,61 @@
+#include <stdio.h>
+#include <ctype.h>
+#include <stdlib.h>
+
+int main() {
+	char input[10];
+	char numbers[4];
+	int date[3]
+	int counter1 = 0, counter2 = 0;
+	fgets(input, 10, stdin);
+
+	for(int i = 0; i < 10; i++){
+		if(!isdigit(input[i]) && input[i] != '.' && input[i] != '\n'){
+			break;	
+		}
+
+		if(input[i] != '.' && input[i] != '\n'){
+			numbers[counter1++] = input[i];
+		}
+		else {
+			date[counter2++] = atoi(numbers);
+			if(counter2 == 1 && (date[0] < 1 || date[0] > 31)){
+				break;
+			}
+			else if(counter2 == 2 && (date[1] < 1 || date[1] > 12)){
+				break;
+			}
+			else if(counter2 == 2 && date[0] > 29){
+				break;
+			}
+			else if (counter2 == 3){
+				date[1] += 7;
+				if(date[0] > 31 && (date[1] == 1 || date[1] == 3 || date[1] == 5 || date[1] == 7 || date[1] == 8 || date[1] == 10 || date[1] == 12)){
+					date[0] -= 31;
+					date[1]++;
+					if(date[1] > 12){
+						date[1] = 1;
+						date[2]++;
+					}
+				}
+				if(date[0] > 30 && (date[1] == 4 || date[1] == 6 || date[1] == 9 || date[1] == 11)){
+                                        date[0] -= 30;
+                                        date[1]++;
+                                }
+				if(date[0] > 29 && date[1] == 2 && date[2] % 4 == 0 && (date[2] % 100 != 0 || (date[2] %100 == 0 && date[2] % 400 == 0))){
+					date[0] -= 29;
+                                        date[1]++;	
+				}
+				else if(date[0] > 28 && date[1] == 2){
+					date[0] -= 28;
+                                        date[1]++;
+				}
+				printf("%d.%d.%d\n", date[0], date[1], date[2]);
+				return 0;
+			}
+		}
+	}
+	puts("Neplatny datum");
+
+	return 0;
+}