2026_TD1_DEV51_Qualite_Algo/exemple.c

#include <stdio.h>

int est_premier(int n) {
    if (n < 2) return 0;
    for (int d = 2; d < n; d++)
        if (n % d == 0) return 0;
    return 1;
}
int somme_chiffres(int n) {
    int s = 0;
    for (; n > 0; n /= 10) s += n % 10;
    return s;
}
int compter_premiers(int limite) {
    int total = 0;
    for (int i = 0; i < limite; i++)
        if (est_premier(i)) total++;
    return total;
}
int premiers_chanceux(int limite) {
    int total = 0;
    for (int i = 0; i < limite; i++)
        if (est_premier(somme_chiffres(i)) && est_premier(i))
            total++;
    return total;
}

int main(void) {
    printf("Nombres premiers < 60000       : %d\n", compter_premiers(60000));
    printf("Premiers « chanceux » < 60000  : %d\n", premiers_chanceux(60000));
    return 0;
}