PAT 1031 Hello World for U

#include<stdio.h>
#include<string.h>

void printspace(int length){
	int i;
	for(i=0;i<length-2;i++){
		printf(" ");
	}
}

int findpropern2(int n){
	int i,j,n1;
	for(i=3;i<=n;i++){
		j = n+2-i;
		if(j%2 == 0) {
			n1 = j/2;
			if(n1 <= i) break;
		}
	}
	return i;
}

int main(){
	char str[50];
	int i,j,t,n,n1,n2,n3;
	while(scanf("%s", str) !=	EOF){
		n = strlen(str);
		n2 = findpropern2(n);
		n1 = n3 = (n + 2 - n2)/2;
		for(i=0,j=n-1;i<n1;i++,j--){
			if(i != n1-1) {
				printf("%c", str[i]);
				printspace(n2);
				printf("%c" ,str[j]);
				printf("\n");
			}else {
				for(t=i;t<=j;t++){
					printf("%c", str[t]);
				}
			}
		}
	}

	return 0;
}