#include <stdio.h>

int main() {
    int dia, mes, a;
    int diasMes;
    int esBisiesto;

    printf("Introduce la fecha (día mes año): \n");
    scanf("%d %d %d", &dia, &mes, &a);

    esBisiesto = (a%4 == 0 && a%100 != 0) || (a%400 == 0);

    switch (mes) {
        case 1: case 3: case 5: case 7: case 8: case 10: case 12:
            diasMes = 31;
            break;
        case 4: case 6: case 9: case 11:
            diasMes = 30;
            break;
        case 2:
            if (esBisiesto) {
            diasMes = 29;
            } else {
            diasMes = 28;
             }
             break;

        default:
            diasMes = 0;
            break;
            }
    if (mes >= 1 && mes <= 12 && dia >= 1 && dia <= diasMes && a > 0) {
        printf("La fecha %02d / %02d / %d es CORRECTA.\n", dia, mes, a);
    } else {
        printf("La fecha %02d / %02d / %d es INCORRECTA.\n", dia, mes, a);
    }

    return 0;
}

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