什么情况？？？

为什么它除了第一次都会先把b+1再相乘呢？？？

#include<bits/stdc++.h>
using namespace std;

const int MAXN = 1e4 + 5;
int a[MAXN],b[MAXN],c[MAXN];
int t[MAXN];
void read(int a,int x[]){
    int tmp = a,d = 0;
    while(tmp > 0){
        d++;
        x[d] = tmp % 10;
        tmp /= 10;
    }
    x[0] = d；

}
void print(int x[]){
    for(int i = x[0];i >= 1;i--)printf("%d",x[i]);
    //printf("\n");
}
void besame(int x[],int y[]){
    for(int i = y[0];i >= 0;i--)y[i] = 0;
    for(int i = 0;i <= x[0];i++)y[i] = x[i];
}
void mul(int x[],int y[],int z[]){
    z[0] = max(x[0],y[0]);
    for(int i = 1;i <= x[0];i++){
        for(int j = 1;j <= y[0];j++){
            z[i + j - 1] += x[i] * y[j];
        }
    }
    for(int i = 2;i <= x[0] + y[0] + 2;i++){
        z[i] += z[i - 1] / 10;
        z[i - 1] %= 10;
        if(z[z[0] + 1] > 0)z[0]++;
        if(z[z[0]] == 0 && z[0] != 1)z[0]--;
    }
}
int main(){
    int n;
    scanf("%d",&n);
    int cnt = 0,tmp = n;
    for(int i = 2;i <= n;i++){
        if(i <= tmp){
            cnt++;
            t[cnt] = i;
            tmp -= i;
        }
    }
    int tcnt = cnt;
    while(tmp > 0){
        t[tcnt]++;
        tmp--;
        tcnt = (tcnt - 2 + n) % n + 1;
    }
    a[0] = 1,a[1] = 1;
    for(int i = 1;i <= cnt;i++){
        //printf("%d\n",t[i]);
        read(t[i],b);
        printf("");
        print(b);
        printf(" * ");
        print(a);
        mul(b,a,c);
        printf(" = ");
        print(c);
        printf("\n");
        besame(c,a);
    }
    print(a);
    return 0;
}