`#include "cassert"
#include "calc.h"
const string a[] = { "零","壹","贰","叁","肆","伍","陆","柒","捌","玖" };
const string b[] = { "元","拾","佰","仟","萬","亿"};
string Xs(const int k[]){
    string c;
    c+=a[k[1]],c+="角",c+=a[k[0]],c+="分";
    return c;
}
string Yuan(const int k[]) {
    string c;
    if (k[0] == 0) {
        if (k[1] == 0) {
            if (k[2] == 0) {
                if (k[3] == 0)c+=a[0];
                else c+=a[k[3]],c+=b[3];
            } else {
                if (k[3] == 0)c+=a[k[2]],c+=b[2];
                else c+=a[k[3]],c+=b[3],c+=a[k[2]],c+=b[2];
            }
        } else {
            if (k[2] == 0) {
                if (k[3] == 0){if(k[1]==1)c+=b[1]; else c+=a[k[1]],c+=b[1];}
                else c+=a[k[3]],c+=b[3],c+=a[0],c+=a[k[1]],c+=b[1];
            } else {
                if (k[3] == 0)c+=a[k[2]],c+=b[2],c+=a[k[1]],c+=b[1];
                else c+=a[k[3]],c+=b[3],c+=a[k[2]],c+=b[2],c+=a[k[1]],c+=b[1];
            }
        }
    }
    else {
        if (k[1] == 0) {
            if (k[2] == 0) {
                if (k[3] == 0)c+=a[k[0]];
                else c+=a[k[3]],c+=b[3],c+=a[0],c+=a[k[0]];
            }
            else {
                if (k[3] == 0)c+=a[k[2]],c+=b[2],c+=a[0],c+=a[k[0]];
                else c+=a[k[3]],c+=b[3],c+=a[k[2]],c+=b[2],c+=a[k[0]];
            }
        } else {
            if (k[2] == 0) {
                if (k[3] == 0)c+=a[k[1]],c+=b[1],c+=a[k[0]];
                else c+=a[k[3]],c+=b[3],c+=a[0],c+=a[k[1]],c+=b[1],c+=a[k[0]];

            }
            else {
                if (k[3] == 0)c+=a[k[2]],c+=b[2],c+=a[k[1]],c+=b[1],c+=a[k[0]];
                else c+=a[k[3]],c+=b[3],c+=a[k[2]],c+=b[2],c+=a[k[1]],c+=b[1],c+=a[k[0]];
            }
        }

    }
    c+=b[0];
    return c;
}
string Wang(const int k[]){
    string c;
    if (k[0] == 0) {
        if (k[1] == 0) {
            if (k[2] == 0) {
                if (k[3] == 0);
                else c+=a[k[3]],c+=b[3];
            } else {
                if (k[3] == 0)c+=a[k[2]],c+=b[2];
                else c+=a[k[3]],c+=b[3],c+=a[k[2]],c+=b[2];
            }
        } else {
            if (k[2] == 0) {
                if (k[3] == 0){if(k[1]==1)c+=b[1]; else c+=a[k[1]],c+=b[1];}
                else c+=a[k[3]],c+=b[3],c+=a[0],c+=a[k[1]],c+=b[1];
            } else {
                if (k[3] == 0)c+=a[k[2]],c+=b[2],c+=a[k[1]],c+=b[1];
                else c+=a[k[3]],c+=b[3],c+=a[k[2]],c+=b[2],c+=a[k[1]],c+=b[1];
            }
        }
    }
    else {
        if (k[1] == 0) {
            if (k[2] == 0) {
                if (k[3] == 0)c+=a[k[0]];
                else c+=a[k[3]],c+=b[3],c+=a[0],c+=a[k[0]];
            }
            else {
                if (k[3] == 0)c+=a[k[2]],c+=b[2],c+=a[0],c+=a[k[0]];
                else c+=a[k[3]],c+=b[3],c+=a[k[2]],c+=b[2],c+=a[k[0]];
            }
        } else {
            if (k[2] == 0) {
                if (k[3] == 0)c+=a[k[1]],c+=b[1],c+=a[k[0]];
                else c+=a[k[3]],c+=b[3],c+=a[0],c+=a[k[1]],c+=b[1],c+=a[k[0]];

            }
            else {
                if (k[3] == 0)c+=a[k[2]],c+=b[2],c+=a[k[1]],c+=b[1],c+=a[k[0]];
                else c+=a[k[3]],c+=b[3],c+=a[k[2]],c+=b[2],c+=a[k[1]],c+=b[1],c+=a[k[0]];
            }
        }

    }
    c+=b[4];
    return c;
}
int wei(int x){
    int i=0;
    for (;x>0;++i,x/=10);
    return i;
}
string convert(double x,string buffer) {
    x *= 100;
    if(x==0){
        buffer+=a[0],buffer+=b[0],buffer+=a[0],buffer+="角",buffer+=a[0],buffer+="分";
        return buffer;
    }
    int d = (int) x;
    int length=wei(d);
    assert(length>=0);
    string wangg,yuann,xss;
    int xs[2];
    int yuan[4];
    int wang[4];
    for (int i = 0; i < 2&&length>=0; ++i, d /= 10,--length)xs[i] = d % 10;
    for (int i = 0; i < 4&&length>=0; ++i, d /= 10,--length)yuan[i] = d % 10;
    for (int i = 0; i < 4&&length>=0; ++i, d /= 10,--length)wang[i] = d % 10;
    if(wang[0]||wang[1]||wang[2]||wang[3]){
    wangg=Wang(wang);
    buffer+=wangg;
    }
    yuann=Yuan(yuan);
    buffer+=yuann;
    xss=Xs(xs);
    buffer+=xss;
    return buffer;
}
`

It will make the Arabic nuimerals to chinese numerals,but when I

why when I change the( for (int i = 0; i < 4&&length>=0; ++i, d /= 10,–length)yuan[i] = d % 10;)length>=0 to length>0,it told me -1073741819 (0xC0000005). and

    if(){     wangg=Wang(wang);     buffer+=wangg;     } 

This part seem not be controlled by

wang[0]||wang[1]||wang[2]||wang[3]

even if I If(0) also have output of this part.

Thank you for your patience,my English really bad.`