c++ - 逻辑错误 : Unable to determine the cause of segmentation fault

Question

    for (i = (routeVector.size () - 1); i >= 0; i--)
    {
        cout << "Connected to -> " << routeVector[i].exitPoint;
        for (j = (routeVector.size () - 1); j >= 0; j--)
        {
            if (routeVector[i].selectedBranchesVector.size() > 0)
            {
                cout << "\n: routeVector[i].selectedBranchesVector[0].connectedExitPoint" <<
routeVector[i].selectedBranchesVector[0].connectedExitPoint;

                ******cout << "\nrouteVector[j].exitPoint:" << routeVector[j].exitPoint;
                if (routeVector[i].selectedBranchesVector[0].connectedExitPoint == routeVector[j].exitPoint)
                {
                    cout << "Connected to -> " << routeVector[i].selectedBranchesVector[0].connectedExitPoint;
                }
            }
        }
    }

盯着的线给我一个段错误，我不明白为什么。

如果“routeVector”在“selectedBranchesVector”中什么都没有，它甚至不会到达里面if。

上述问题的原因可能是什么？

编辑 1:

为了让问题更清楚，我打印了语句的两个条件，错误显示在凝视的行上。

结构是:

typedef struct branch
{
    unsigned int distance;
    int          connectedExitPoint;
} branch;

typedef struct route
{
    int    exitPoint;
    vector <branch> selectedBranchesVector;
} route;

vector <route> routeVector;

Answer 1

这取决于 i 和 j 的类型 - 如果 i 和 j 是 unsigned，上面的循环会非常愉快地循环回来——这可能是正在发生的事情——打印索引，你会看到……