package main

func EsNumeroValido(value string) bool {
	if len(value) == 0{
		return false
	}
	if value [0] == '-' && len(value) == 1{
		return false
	}
	var dotCounter int
	for i:= 0; i < len(value); i++{
		//first rule
		if i == 0{
			if value[i] == '-' || (value[i] >= '0' && value[i] <= '9') {
				continue
			}
			return false
		}else{
			if value[i] == '.'{
				dotCounter++
				continue
			}
			if (value[i] >= '0' && value[i] <= '9') {
				continue
			}
			return false 
		}
	}
	if dotCounter > 1{
		return false
	}
	if value[len(value)-1] == '.'{
		return false
	}
	return true
}