c语言实现地点查询次数记录，并将其记录到txt文档中

以下是一个简单的C语言程序，可以实现查询次数的记录，并将其记录到txt文档中：

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

#define MAX_LOCATION_LENGTH 50 // 地点名称最大长度

/* 定义地点结构体 */
typedef struct Location {
    char name[MAX_LOCATION_LENGTH]; // 地点名称
    int count; // 查询次数
} Location;

/* 定义函数：从txt文件中读取地点列表 */
int read_locations_from_file(char* filename, Location** locations, int* num_locations) {
    FILE* fp = fopen(filename, "r");
    if (fp == NULL) {
        printf("Error: cannot open file %s\n", filename);
        return -1;
    }

    int max_locations = 10;
    *locations = (Location*)malloc(max_locations * sizeof(Location));
    *num_locations = 0;

    char line[MAX_LOCATION_LENGTH + 10];
    while (fgets(line, MAX_LOCATION_LENGTH + 10, fp) != NULL) {
        if (*num_locations >= max_locations) {
            max_locations *= 2;
            *locations = (Location*)realloc(*locations, max_locations * sizeof(Location));
        }
        sscanf(line, "%s %d", (*locations)[*num_locations].name, &((*locations)[*num_locations].count));
        (*num_locations)++;
    }

    fclose(fp);
    return 0;
}

/* 定义函数：向txt文件中写入地点列表 */
int write_locations_to_file(char* filename, Location* locations, int num_locations) {
    FILE* fp = fopen(filename, "w");
    if (fp == NULL) {
        printf("Error: cannot open file %s\n", filename);
        return -1;
    }

    for (int i = 0; i < num_locations; i++) {
        fprintf(fp, "%s %d\n", locations[i].name, locations[i].count);
    }

    fclose(fp);
    return 0;
}

/* 定义函数：查询某个地点 */
void query_location(Location* locations, int num_locations, char* name) {
    for (int i = 0; i < num_locations; i++) {
        if (strcmp(locations[i].name, name) == 0) {
            locations[i].count++;
            printf("%s has been queried %d times\n", name, locations[i].count);
            return;
        }
    }
    printf("%s has not been queried before\n", name);
}

int main() {
    Location* locations;
    int num_locations;

    /* 从txt文件中读取地点列表 */
    if (read_locations_from_file("locations.txt", &locations, &num_locations) != 0) {
        return -1;
    }

    /* 进行地点查询 */
    char name[MAX_LOCATION_LENGTH];
    while (1) {
        printf("Please input a location name (q to quit):\n");
        scanf("%s", name);
        if (strcmp(name, "q") == 0) {
            break;
        }
        query_location(locations, num_locations, name);
    }

    /* 将地点列表写入txt文件 */
    if (write_locations_to_file("locations.txt", locations, num_locations) != 0) {
        return -1;
    }

    free(locations);
    return 0;
}

这个程序中，我们定义了一个地点结构体，包含地点名称和查询次数两个属性。我们首先从txt文件中读取地点列表，然后进行地点查询，如果查询到了某个地点，则将其查询次数加1。最后，我们将更新后的地点列表写入txt文件中。

你可以在程序中修改文件名和文件路径，以适应你的需要。