Submission #1228776

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Source Code Expand

#include <cstdio>

int n;
char s[1000100],t[1000100];
int sum[1000100];
int w[26][1000100];

int main(void)
{
	int i;
	int x;
	char z;
	int result = 0;
	
	scanf("%d %s %s",&n,s,t);
	
	for(i = 0;i < n;++i)
		s[i] -= 'a',t[i] -= 'a',w[s[i]][++w[s[i]][0]] = i;

	x = n;
	for(i = n - 1;i >= 0;--i)
	{
		if((i < x && s[i] == t[i]) || (i >= x && t[i] == z))
			continue;
			
		int *h = w[t[i]],e = i < x ? i : x;
		while(h[0] && h[h[0]] >= e)
			--h[0];
		if(!h[0])
			return puts("-1"),0;
		z = t[i];
		++sum[x = h[h[0]]];
		--sum[i + 1];
	}
	
	for(i = 1;i <= n;++i)
		sum[i] += sum[i - 1];
	for(i = 0;i < n;++i)
		result = result > sum[i] ? result : sum[i];
	printf("%d\n",result);
	
	return 0;
}

Submission Info

Compile Error

./Main.cpp: In function ‘int main()’:
./Main.cpp:15:26: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d %s %s",&n,s,t);
                          ^

Judge Result