c - C 中带条件的 Goto 语句

Question

如何使用 if 和 else 条件执行 goto 语句我希望我的用户决定他/她是否想要重新开始

 loop1 :
        printf("how many dagre entering ? \n");
        scanf("%d", &NumOfGrade);

        for ( i = 0 ; i < NumOfGrade ; i ++ ) {

            printf("\nenter the grade\n");
            scanf("%d", &grade);

            totalGrade += grade ;

            if ( grade < 12 )
            failsCount ++;
        }

        ave = (float) totalGrade / NumOfGrade ;

        printf("the ave of ur grade are  : \n");
        printf("%.2f\n", ave);
        printf("%d subj fails\n", failsCount);

        printf("do you want to startover ? (Y or N) \n");
        ans = getchar();
        if ( ans == 'Y') 
            goto loop1 ;

它不会循环1，我不明白为什么。

Answer 1

您没有清除输入缓冲区，请尝试以下操作:

loop1 :
    printf("how many dagre entering ? \n");
    scanf("%d", &NumOfGrade);

    for ( i = 0 ; i < NumOfGrade ; i ++ ) {

        printf("\nenter the grade\n");
        scanf("%d", &grade);

        totalGrade += grade ;

        if ( grade < 12 )
        failsCount ++;
    }

    ave = (float) totalGrade / NumOfGrade ;

    printf("the ave of ur grade are  : \n");
    printf("%.2f\n", ave);
    printf("%d subj fails\n", failsCount);

    printf("do you want to startover ? (Y or N) \n");
    __fpurge(stdin); // clear your input buffer, on window, try fflush(stdin)
    ans = getchar();
    if ( ans == 'Y') 
        goto loop1 ;