关于C题的分讨

在本人大力分讨过后还是一直WA，但是不知道为什么WA，有无大佬指出哪里出问题了Orz

/*
 * @Author: Aisaka_Taiga
 * @Date: 2023-11-03 19:45:08
 * @LastEditTime: 2023-11-03 21:35:15
 * @LastEditors: Aisaka_Taiga
 * @FilePath: \Desktop\T3.cpp
 * The heart is higher than the sky, and life is thinner than paper.
 */
#include <bits/stdc++.h>

#define int long long
#define N 200100

using namespace std;

inline int read()
{
    int x = 0, f = 1;
    char c = getchar();
    while(c < '0' || c > '9'){if(c == '-') f = -1; c = getchar();}
    while(c <= '9' && c >= '0') x = (x << 1) + (x << 3) + (c ^ 48), c = getchar();
    return x * f;
}

int n, m, k, a[N], sum, cnt;

inline void work()
{
    int ans = 0;
    n = read(), m = read(), k = read();
    if(k == 1) return cout << m << endl, void();
    if(k % 2 == 0)
    {
        int kk = n % k;
        if(kk % 2 == 1) ans ++, kk --;
        if(m >= kk / 2) ans += (m - kk / 2) % (k / 2);
        else ans += m;
        cout << ans << endl;
        return ;
    }
    int xx = k / 2;//一团最多多少女的
    int kk = m / xx;//几团
    int cc = m - kk * xx;//多余的女的
    if(n >= kk)
    {
        n -= kk;//还有多少男的没成团
        if(n + cc * 2 < k) return cout << n + cc << endl, void();
        n -= (k - cc * 2);
        n %= k;
        if(n / 2 <= m) return cout << (n + 1) / 2 << endl, void();
        cout << n - m << endl;
        return ;
    }
    cout << (kk - n) * xx + cc << endl;
    return ;
}

signed main()
{
    int T = read();
    while(T --) work();
    return 0;
}
/*
2
1 1 4
4 5 2
*/