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#include <iostream>
//#include <gtest/gtest.h>
const int FIB_PISANO_PERIOD_FOR_TEN = 60;
static int getFibNModM(long n) {
long r = n % FIB_PISANO_PERIOD_FOR_TEN;
if (r == 0)
return 0;
int firstN = 0;
int secondN = 1;
int tempHolder = 1;
for (int i = 1; i < r; i++) {
tempHolder = (firstN + secondN) % 10;
firstN = secondN;
secondN = tempHolder;
}
return secondN;
}
static int getLastDigit(long n) {
if (n <= 1)
return (int) n;
int result = getFibNModM(n + 2);
if (result == 0)
return 9;
else
return result - 1;
}
//TEST(FibSumLastDigitTest, Zero) {
// ASSERT_EQ(getLastDigit(0), 0);
//}
//TEST(FibSumLastDigitTest, One) {
// ASSERT_EQ(getLastDigit(1), 1);
//}
//TEST(FibSumLastDigitTest, Six) {
// ASSERT_EQ(getLastDigit(6), 0);
//}
//TEST(FibSumLastDigitTest, Nine) {
// ASSERT_EQ(getLastDigit(9), 8);
//}
//TEST(FibSumLastDigitTest, OneHundred) {
// ASSERT_EQ(getLastDigit(100), 5);
//}
//TEST(FibLastDigitTest, One) {
// ASSERT_EQ(getFibNModM(239, 1000), 161);
//}
//
//TEST(FibLastDigitTest, Three) {
// ASSERT_EQ(getFibNModM(2816213588, 30524), 10249);
//}
//TEST(FibLastDigitTest, Forty) {
// ASSERT_EQ(1344, getGCD(1344, 1344));
//}
//
//TEST(FibLastDigitTest, ThreeThreeOne) {
// ASSERT_EQ(4, getGCD(14159572, 63967072));
//}
//
//TEST(FibLastDigitTest, ReverseAB) {
// ASSERT_EQ(4, getGCD(14159572, 63967072));
//}
int main() {
long n;
std::cin >> n;
int c = getLastDigit(n);
std::cout << c << '\n';
}
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