public static int CalculaDias(int a, int m)throws IOException{

if ( (m == 1) || (m == 3) || (m == 5) || (m == 7) || (m == 8) || (m == 10) || (m == 12) ){

return 31;

}else if ( (m == 4) || (m == 6) || (m == 9) || (m == 11) ) {

return 30;

}else if (m == 2){

if ( ( ( ( a % 4 ) == 0 ) && ( ( a % 100 ) ) != 100 ) || ( ( a % 400 ) == 0 ) ) {

return 29;

}

return 28;

}else{

return -1;

}

}