Understanding the ‘continue’ Statement in C Programming

The following is a detailed analysis of the usage of the <span>continue</span> statement in C language:

1. Core Functionality

‌Skip the current loop iteration‌immediately terminates the execution of the current loop body and directly enters the loop condition check (for/while) or iteration step (for loop)

for(int i=0; i<10; i++) {
if(i%2 == 0) continue;  // Skip even numbers
printf("%d ", i);       // Only output odd numbers
}

2. Typical Application Scenarios

1. ‌Filtering Invalid Data‌skip data items that do not meet the criteria during input processing

   while(scanf("%d", &num) != EOF) {
   if(num < 0) continue;  // Ignore negative numbers
       process(num);
   }

2. ‌Error Handling‌continue subsequent processing when encountering non-fatal errors in a loop

   for(int i=0; i<MAX_RETRY; i++) {
   if(!sensor_read()) continue;  // Retry on read failure
   break;
   }

3. ‌Performance Optimization‌skip unnecessary iterations in advance to save CPU time

   for(int i=0; i<BUF_SIZE; i++) {
   if(buffer[i] == 0) continue;  // Skip empty data
       complex_processing(buffer[i]);
   }

3. Difference Between <span>break</span> and <span>continue</span>

4. Precautions

1. ‌Nested Loops‌only affects the innermost loop and cannot control across loops

   for(int i=0; i<3; i++) {
   for(int j=0; j<3; j++) {
   if(j==1) continue;  // Only skip the j=1 case in the inner loop
   printf("%d-%d ",i,j);
       }
   }
   /* Output: 0-0 0-2 1-0 1-2 2-0 2-2 */

2. ‌Switch Statement Disabled‌<span>continue</span><code><span> cannot be used in switch structures (unlike languages like Java)</span>

3. ‌Loop Type Influence‌

• ‌while/do-while‌: directly jumps to the condition check
• ‌for loop‌: executes the iteration expression first, then checks the condition
• Proper use of continue can enhance code readability and execution efficiency, but excessive use may lead to control flow confusion; it is recommended to use comments to explain the skipping logic.