for语句疑问

main()
{int a,n;
long j;
printf("请输入2个正整数'a' 'n'\n");
scanf("%d%d",&a,&n);
j=a;
for(;n>1;n--)
{a=a*10;j=j+a;}
printf("%ld",j);
getch();}
我想输出n个a,n小于5时程序正确,当输入n大于5时输出的不是我要的结果;
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I don't know the meaning of it!

Could you tell me? Thank you !

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main()
{int n;
long j,a;
printf("请输入2个正整数'a' 'n'\n");
scanf("%ld%d",&a,&n);
j=a;
for(;n>1;n--)
{a=a*10;j=j+a;}
printf("%ld",j);
getch();}
明白了 谢谢
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想知道整型和长整型相加后是不是长整型？
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