Question

我有一个项目，我正在从斯坦福的CS106B开始工作，这是一个令人难以置信的问题。我有一个struct，dieLocation，它应该代表我的Boggle板上模具的位置。

typedef struct dieLocation {
    int row, column; 
}dieLocation;

然后我有了这段代码：

Set<dieLocation> Boggle::getUnmarkedNeighbors(Grid<bool> &markedLocations, dieLocation currentDie) {
    int row = currentDie.row;
    int column = currentDie.column;
    Set<dieLocation> neighbors;
    for(int currRow = row - 1; currRow < row + 1; currRow++) {
        for(int currCol = column - 1; currCol < column + 1; currCol++) {
            //if neighbor is in bounds, get its row and column.
            if(markedLocations.inBounds(currRow, currCol)) {
                //if neighbor is unmarked, add it to the  neighbors set
                if(markedLocations.get(currRow, currCol)) {
                    dieLocation neighbor;
                    neighbor.row = currRow;
                    neighbor.column = currCol;
                    neighbors.add(neighbor);
                }
            }
        }
    }
    return neighbors;
}

我尝试在Qt Creator中构建此项目，但我一直收到错误，即：不匹配＆＃39;运算符＆lt;＆＃;;（操作数类型是const dieLocation和const dieLocation）

我的代码所做的是，它将传递的dieLocation的行和列分配给它们各自的变量。然后它循环遍历每一行，从少于传递的行开始，到另一行列也一样。但是，我相信我在for循环中比较整数，但它说我比较dieLocations？有谁知道为什么会这样？

Answer 1

operator <用于Set内部，用于订购商品。您应该为struct dieLocation定义它。例如：

inline bool operator <(const dieLocation &lhs, const dieLocation &rhs)
{
    if (lhs.row < rhs.row)
        return true;
    return (lhs.column < rhs.column);
}

与'operator＆lt;'不匹配错误。 C ++

1 个答案: