Expected ‘)’ before ‘;’ token G++

Question

GCC keeps telling me:

expected ‘)’ before ‘;’ token,
expected primary-expression before ‘)’ token
expected ‘;’ before ‘)’ token

And I could not find the problem. Here is the function that have the problem:

void prim(){
    prepararEstructuras();
    int min,k;  
    for(int i=1;i<nnodos;i++){
        min = menorCoste[1];
        k = 1;
        for(int j=2;i<nnodos;j++)
            if(menorCoste[j] < min){
                min = menorCoste[j];
                k = j;
            }
        solucion[k][masCercano[k]] = G[k][masCercano[k]];
        menorCoste[k] = infinito;
        for(int j=1;j<nnodos;j++)
            if(G[k][j] < menorCoste[j] && menorCoste[j]!=infinito){
                menorCoste[j] = G[k][j];
                masCercano[j] = k;
            }                   
    }
}

Here is the line that cause the problem:

if(G[k][j] < menorCoste[j] && menorCoste[j]!=infinito){

And here are my variables:

#define MAX_NODOS 20000
#define infinito 10000;

int nnodos;
int nAristas;
int G[MAX_NODOS][MAX_NODOS]; 
int solucion[MAX_NODOS][MAX_NODOS];
int menorCoste[MAX_NODOS];
int masCercano[MAX_NODOS];

What effect does this macro have on that line? #define infinito 10000; — , Jan 02 '12 at 01:08
While what you have is valid, I highly suggest putting those `{}` around those multi-line `for` loops, it's more difficult to read and easier to mess things up. — Andrew Marshall, Jan 02 '12 at 01:11

score 12 · Accepted Answer · answered Jan 02 '12 at 01:06

12

You have an extra semicolon in your macro.

#define infinito 10000;
                      ^

Get rid of it.

As it is, your line gets expanded to this:

if(G[k][j] < menorCoste[j] && menorCoste[j]!=10000;){
                                                  ^ does not belong here

Alternatively, don't use macros at all:

const int MAX_NODOS = 20000;
const int infinito = 10000;

answered Jan 02 '12 at 01:06

Mysticial

464,885
45
335
332

Thank you very much your answer is accpeted – Youssef Khloufi Jan 02 '12 at 01:09
Though, you really should read about preprocessor vs. actual C Code - to understand why such an innocent additional semi-colon ****** your code up ;) – Frunsi Jan 02 '12 at 02:41

score 2 · Answer 2 · answered Jan 02 '12 at 01:14

2

Please, learn to use a GOOD STYLE. Omitting brackets in outer statements (e.g. statements that contain other statements) is an extraordinarily BAD style.

However, your actual bug lies in some pre-processor statement and its resulting code: #define infinito 10000; results in an extra semi-colon in-between an expression where you do not expect such an additional expression. Particularly where you will not expect a semi-colon at all.

answered Jan 02 '12 at 01:14

Frunsi

7,099
5
36
42

What can only be worse style is giving something called infinito a set value. – casualcoder Jan 02 '12 at 03:06

Expected ‘)’ before ‘;’ token G++

2 Answers2