题解 | #多组_带空格的字符串_T组形式#

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

#define MAX_LENGTH 100005

void reverse_and_remove_spaces(char* str, char* result) {
    int len = strlen(str);
    int index = 0;

    // Remove spaces
    for (int i = 0; i < len; i++) {
        if (str[i] != ' ') {
            result[index++] = str[i];
        }
    }
    result[index] = '\0';  // Null-terminate the result string

    // Reverse the result string
    int start = 0;
    int end = index - 1;
    while (start < end) {
        char temp = result[start];
        result[start] = result[end];
        result[end] = temp;
        start++;
        end--;
    }
}

int main() {
    int t;
    scanf("%d", &t);

    // To handle large inputs efficiently
    char input[MAX_LENGTH];
    char result[MAX_LENGTH];

    while (t--) {
        int n;
        scanf("%d", &n);
        getchar();  // Consume the newline character left by scanf

        // Read the whole line including spaces
        fgets(input, MAX_LENGTH, stdin);

        // Remove trailing newline character
        input[strcspn(input, "\n")] = '\0';

        reverse_and_remove_spaces(input, result);

        // Print the result
        printf("%s\n", result);
    }

    return 0;
}