How to solve the issue of invalid use of continue in C+…

In C++, the continue statement is used to skip the remaining statements in the current loop and begin the next iteration of the loop. If the continue statement is invalid, it may be due to its placement in a position where continue is not allowed, or due to an incorrect loop condition.

Here are some common issues and solutions that may cause “continue” to be ineffective.

1. The continue statement does not work within a switch statement because switch is a selection structure, not a loop structure. To overcome this, use a while or for loop with the switch statement to achieve iteration.
2. The continue statement is placed inside the inner loop of a nested loop: if the continue statement is inside the inner loop, it will only skip the remaining statements of the inner loop and will not jump to the outer loop. The solution is to use a label to identify the outer loop, and then specify the label in the continue statement.

for (int i = 0; i < 5; i++) {
    for (int j = 0; j < 5; j++) {
        if (j == 2) {
            continue; // 无效的continue语句
        }
        cout << i << " " << j << endl;
    }
}

Solution:

for (int i = 0; i < 5; i++) {
    for (int j = 0; j < 5; j++) {
        if (j == 2) {
            goto skip; // 使用标签和goto语句跳过内部循环迭代
        }
        cout << i << " " << j << endl;
    }
    skip:;
}

1. keep going
2. keep going

If none of the above methods can solve the problem, it is recommended to provide more code examples and a detailed description of the issue in order to better understand the problem and provide a more specific solution.