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How many parameters can I pass by reference in C++, without getting abnormal behavior

I had a problem with a function:

int parsearRestricciones(char linea[], unsigned int& x, unsigned int& y, unsigned int& tiempo, char restric[])

Inside that function I parse linea[].

The input consists in: three unsigned integers, and a string of punctuation characters. I need to read them that way. The problem ocurrs when I assign atoi(linea+offset) to variable tiempo. Outside the function (i.e., in main() ), the value of tiempo is not the same that it's inside. I had the problem only with tiempo (I replaced x,y and tiempo by a pointer to struct. It works)

What could be the problem?

Thanks for your help.

-----edit-again

The full code:

#include <iostream>
#include <cstdio>
#include <cstdlib>
#include <ctype.h>
#include <cassert>

#define MAX_RESTRIC 3  // Tres sentidos. Si hay 4, se usa '+'
#define MAX_LINEA 80
#define entrada cin


using namespace std;

int parsearRestricciones(char *linea, unsigned int& x, unsigned int& y, unsigned int& t, char *restric) {
// ! solo funciona si x,y,t,restric estan en una misma linea (i.e. no hay CR LF)

int i=0, j=0;

//Parsea x de la casilla
x = atol(linea+i);//strtol(linea,(char**)NULL,10);

while (isdigit(linea[i])) i++;
while (isspace(linea[i])) i++;

//Parsea y de la casilla
y = atol(linea+i);

while (isdigit(linea[i])) i++;
while (isspace(linea[i])) i++;
if(linea[i] == '\0')
    return -1;

//Parsea tiempo
t = atol(linea+i);
cout << "---" << t << endl;

while (!ispunct(linea[i])) i++;

//Parsea restricciones
while (linea[i] != '\0' && linea[i] != ' '){
    restric[j] = linea[i];
    i++; j++;
}
restric[j]='\0';

return 1;

}


int main (int argc, char** argv)
{
// Sugerencia de argumentos
// --d  (por Dijkstra)
// --axe  (por A*, distancia euclideana)
// --axm  (por A*, distancia manhattan)

// y dos màs que veremos luego :)

unsigned int X, Y;
unsigned int xi, yi;
unsigned int xf, yf;

unsigned int x,y,tiempo;

char restricciones[MAX_RESTRIC + 1];


//Buffer para parsear las lineas con restricciones
char linea[MAX_LINEA + 1];

bool finCasos = false;
bool siguienteCaso = false;


while (!finCasos)
{

    if (siguienteCaso){
        // Se leyó otro mapa antes que éste (hubo parseo, y quedo en xcasilla,ycasilla)
        X = x;
        Y = y;
        siguienteCaso = false;

    } else {
        // Sino, lee por primera vez las dimensiones del mapa
        entrada >> X >> Y;
    }

    if (开发者_运维百科 X == 0  &&  Y == 0 )
        finCasos = true;

    else {

        entrada >> xi >> yi;

        entrada >> xf >> yf;

        // Lee restricciones hasta que encuentra una linea sin ellas (sin tiempo ni direccion)
        // se asumira, que corresponde a las dimensiones del siguiente caso, y los usará en la siguiente
        // iteracion
        while(!siguienteCaso) {

            cin.get(); //lee un '\0' que quedó (?)
            cin.getline(linea, MAX_LINEA+1);

            if ( parsearRestricciones(linea,x,y,tiempo, restricciones) == -1 ) {
                siguienteCaso = true;

            } else {

                cout << "X = " << x << endl;
                cout << "Y = " << y << endl;
                cout << "tiempo = " << tiempo << endl;
                cout << "restric = " << restricciones << endl;
                int j=0;
                cout << "restric = " ;
                while(restricciones[j]!='\0'){
                    cout << restricciones[j];j++;}
                cout << endl;

                //-- agregar datos al grafo/mapa
            }

        }

        // Resolver usando algun algoritmo
        //--- resolver(MAPA)

    }

}


return 0;
}

CFLAGS. -Wall -pipe -g -ggdb -DONLINE_JUDGE -DNDEBUG (The Makefile also builds another source, for uvaonlinejudge)

Input:

101
10
1
1
2
2
1000 10000  100000 +++++

Output:

---100000
X = 1000
Y = 10000
tiempo = 65579
restric = +++++
restric = +++++
^X^C (I did break)

I just tested the program in Windows (using Code::Blocks, default settings) and it worked :/

By the way, I'm using Ubuntu in Virtualbox

Could you tell me what I'm doing wrong?


How many parameters can I pass by reference in C++, without getting abnormal behavior?

As many as you want to!


There is no such limit. However, your function does not use tiempo in any way, it uses some variable called t instead: t = atol(linea+i);

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