Submission #1819807

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Source Code Expand

#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <cctype>
#include <cmath>
#include <algorithm>
#define rep(i, a, b) for (int i = (a), _ = (b); i <= _; ++ i)
#define per(i, a, b) for (int i = (a), _ = (b); i >= _; -- i)
#define For(i, a, b) for (int i = (a), _ = (b); i < _; ++ i)
#define ri rd<int>
using namespace std;
const int maxN = 1e6 + 7;

template<class T> inline T rd() {
	bool f = 1; char c = getchar(); for (; !isdigit(c); c = getchar()) if (c == '-') f = 0;
	T x = 0; for (; isdigit(c); c = getchar()) x = x * 10 + c - 48; return f ? x : -x;
}

inline void NIE() {
	puts("-1");
	exit(0);
}

int n;
char s[maxN], t[maxN];
char nw[maxN], col;

int main() {

	n = ri();
	scanf("%s%s", s+1, t+1);

	int j = n+1, res = 0;
	per (i, n, 1) {
		if (j <= i) s[i] = col;
		if (s[i] == t[i]) continue;
		if (j <= i) ++res;
		else if (j == n+1) ++res, j = i;
		if (j > i) j = i;
		for (; j && s[j] != t[i]; -- j);
		if (s[j] != t[i]) NIE();
		col = t[i];
	}
	printf("%d\n", res);

	return 0;
}

Submission Info

Compile Error

./Main.cpp: In function ‘int main()’:
./Main.cpp:31:25: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result]
  scanf("%s%s", s+1, t+1);
                         ^

Judge Result