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C/factorial.c

@@ -0,0 +1,20 @@
+#include <stdio.h>
+
+int main() {
+    int num;
+    unsigned long long fact = 1;
+
+    printf("Enter a non-negative integer: ");
+    scanf("%d", &num);
+
+    if (num < 0) {
+        printf("Factorial is not defined for negative numbers.\n");
+    } else {
+        for (int i = 1; i <= num; i++) {
+            fact *= i;
+        }
+        printf("Factorial of %d = %llu\n", num, fact);
+    }
+
+    return 0;
+}