#include<stdio.h>void main(){ int i,j,k,m,n; char ch; printf("Enter n:\n"); scanf("%d",&n); for(i=1;i<=n;i++) {ch='a'+i-1; m=2*i-1;} for(k=n;k>i;k--) putchar(" "); for(j=1;j<=m;j++) putchar(ch); }}是哪里错了