/* Author: Raul Vasile
 * Mail: [email protected]
 */

#include <stdio.h>

// Rezolvare problema
int solve(int zeros) {
    int number = 1;

    while (zeros != 0) {
        number++;

        if (number % 10 == 5) {
            zeros--;
            
            if (number % 100 % 25 == 0) {
                zeros--;
            }
        }

        if (number % 10 == 0) {
            zeros--;
        }
    }

    return number;
}

int main(int argc, char* argv[]) {
    // Declarare variable
    int zeros;

    // Declarare fisiere
    FILE *input, *output;

    // Deschidere fisiere
    input = fopen("fact.in", "r");
    output = fopen("fact.out", "w");

    // Verificare fisiere
    if (input == NULL || output == NULL) {
        printf("Error opening files");
        
        return 0;
    } else {
        fscanf(input, "%d", &zeros);

        fprintf(output, "%d\n", solve(zeros));
    }

    return 0;
}