一道考验细节的题

最后是？：运算符用错了

代码如下：

#include<stdio.h>
#include<string.h>
typedef struct Grade{
    int num;
    int inv;
}Grade;
Grade tmp[10];
int n, m, g, interval[10] = {0};

int main(void)
{
    scanf("%d%d%d", &n, &m, &g);
    int num = 100 / m;
    for(int i = 0, grade; i < n; i++)
    {
        scanf("%d", &grade);
        if(grade != 100)
            interval[(int)(grade / num)]++;
        else
            interval[m - 1]++;
    }
    //任务一
    if(g == 0 || g == 1)
    {
        for(int i = 0; i < m; i++)
            tmp[i].num = interval[i], tmp[i].inv = i;
        for(int i = 0; i < m - 1; i++)
            for(int j = i + 1; j < m; j++)
                if(tmp[i].num < tmp[j].num || (tmp[i].num == tmp[j].num && tmp[i].inv > tmp[j].inv))
                {
                    tmp[i].num ^= tmp[j].num ^= tmp[i].num ^= tmp[j].num;
                    tmp[i].inv ^= tmp[j].inv ^= tmp[i].inv ^= tmp[j].inv;
                }//交换
        for(int i = 0; i < m; i++)
        {
            if(tmp[i].num == 0)  break;
            if(tmp[i].inv == m - 1)
                printf("[%2d,%3d]: %d\n", tmp[i].inv * num, (tmp[i].inv + 1) * num, tmp[i].num);
            else
                printf("[%2d,%3d): %d\n", tmp[i].inv * num, (tmp[i].inv + 1) * num, tmp[i].num);
        }
    }
    if(g == 0)  putchar('\n');
    //任务二
    if(g == 0 || g == 2)
    {
        int maxn = 0;
        for(int i = 0; i < m; i++)
            maxn = (maxn > interval[i]) ? maxn : interval[i];
        if(maxn > 50)
        {
            for(int i = 0; i < m; i++)
                interval[i] = interval[i] * 50 / maxn;
        }
        for(int i = 0; i < m; i++)
        {
            if(i == m - 1)
                printf("[%2d,%3d]:", i * num, (i + 1) * num);
            else
                printf("[%2d,%3d):", i * num, (i + 1) * num);
            for(int j = 0; j < interval[i]; j++)
                putchar('*');
            putchar('\n');
        }
    }

    return 0;
}