由於Visual Studio Ultimate 2013中的scanf_s，程序崩潰了

Question

我剛剛開始使用C語言，因為我的大學有一些編程課程。 當我們在Dev C ++程序中編程時，我從高中知道一點C。 現在我們需要使用Visual Studio，我編寫的下一個程序在Dev C ++中工作正常，但在輸入名稱后崩潰了。 在開發C ++中，我從strcat和scanf刪除_s ，它完美無缺。 有人可以幫我解決這個問題嗎？ 這個程序是關於輸入一個名字，它應該隨機設置你在這兩個團隊中的一個。

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

int main() {
    int maxPlayers = 16, player, teamForming, numPlayer1 = 0, numPlayer2 = 0;
    char blueTeam[256] = "", redTeam[256] = "", name[16];
    for (player = 1; player <= maxPlayers; player++) {
        printf("\nEnter a name of %d. player : ", player);
        scanf_s(" %s", name);
        teamForming = rand() % 2;
        if (teamForming == 0) {
            if (numPlayer1 == 8) {
                strcat_s(redTeam, name);
                strcat_s(redTeam, " ");
                numPlayer2++;
                break;
            }
            strcat_s(blueTeam, name);
            strcat_s(blueTeam, " ");
            numPlayer1++;
        } else {
            if (numPlayer2 == 8) {
                strcat_s(blueTeam, name);
                strcat_s(blueTeam, " ");
                numPlayer1++;
                break;
            }
            strcat_s(redTeam, name);
            strcat_s(redTeam, " ");
            numPlayer2++;
        }
    }
    printf("\nBlue team : %s.\n", blueTeam);
    printf("\nRed team : %s.\n", redTeam);
    return 0;
}

Answer 1

scanf_s和scanf語義略有不同：對於s和[格式，您必須傳遞目標數組的大小：

scanf_s(" %s", name, sizeof(name));

類似地， strcat_s作為目標數組和源字符串之間的第三個參數，即目標數組中元素的數量。

以下是您的代碼的修改版本：

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

int main(void) {
    int maxPlayers = 16, player, teamForming, numPlayer1 = 0, numPlayer2 = 0;
    char blueTeam[256] = "", redTeam[256] = "", name[16];
    for (player = 1; player <= maxPlayers; player++) {
        printf("\nEnter a name of %d. player : ", player);
        scanf_s(" %s", name, sizeof(name));
        teamForming = rand() % 2;
        if (teamForming == 0) {
            if (numPlayer1 == 8) {
                strcat_s(redTeam, sizeof(redTeam), name);
                strcat_s(redTeam, sizeof(redTeam), " ");
                numPlayer2++;
                break;
            }
            strcat_s(blueTeam, sizeof(blueTeam), name);
            strcat_s(blueTeam, sizeof(blueTeam), " ");
            numPlayer1++;
        } else {
            if (numPlayer2 == 8) {
                strcat_s(blueTeam, sizeof(blueTeam), name);
                strcat_s(blueTeam, sizeof(blueTeam), " ");
                numPlayer1++;
                break;
            }
            strcat_s(redTeam, sizeof(redTeam), name);
            strcat_s(redTeam, sizeof(redTeam), " ");
            numPlayer2++;
        }
    }
    printf("\nBlue team : %s.\n", blueTeam);
    printf("\nRed team : %s.\n", redTeam);
    return 0;
}