C语言字符串逆序输出问题求助：输出格式不符预期

Hey there! Let's break down why your code isn't giving you the expected output and fix it step by step.

The Problem Breakdown #

You want to take a string like "Table" and output suffixes starting from the shortest (last character) to the full string, in their normal order, separated by spaces: "e le ble able Table".

Right now, your code is doing three things wrong:

1. It prints each suffix in reverse order (hence "e el elb elba elbaT" instead of the correct forward suffixes).
2. It doesn't add spaces between each suffix, so everything runs together.
3. fgets includes the newline character from your input, which could cause unexpected behavior if not handled.

The Fixed Code #

Here's the adjusted code that produces your desired output:

#include <stdio.h>
#include <string.h>

int main(int argc, char *argv[]) {
    char str[100];
    printf("Enter a string: ");
    fgets(str, 100, stdin);
    
    // Remove the newline character added by fgets
    size_t len = strlen(str);
    if (len > 0 && str[len - 1] == '\n') {
        str[len - 1] = '\0';
        len--;
    }

    // Loop through each suffix length from 1 to full string length
    for (int i = 1; i <= len; i++) {
        // Calculate the starting index of the current suffix
        int start = len - i;
        // Print each character of the suffix in normal order
        for (int j = start; j < len; j++) {
            printf("%c", str[j]);
        }
        // Add a space after each suffix
        printf(" ");
    }
    printf("\n"); // Add a final newline for clean output
    return 0;
}

Key Changes Explained #

• Handling fgets newline: We check if the last character is a newline and replace it with a null terminator. This ensures we're only working with the actual input string, no extra hidden characters.
• Forward suffix printing: Instead of looping from the end of the string backwards, we calculate the starting index of each suffix (e.g., for length 2 in "Table", start at index 3 which is 'l') and print characters from that start to the end of the string.
• Space separation: After each suffix, we print a space to match your desired format.

Testing this with input "Table" will give you exactly: e le ble able Table

内容的提问来源于stack exchange，提问作者Kazizo