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    <p>Unlike the numeric conversion specifiers and <code>%s</code>, the <code>%c</code> conversion specifier does not skip blanks. Thus, given your example inputs, the <code>%*c</code> is reading the blank before the operator. You could sensibly use:</p> <pre><code>while (sscanf(matrix[i][c] + offset, " %c%d %c %c%d", &amp;col1, &amp;row1, &amp;op, &amp;col2, &amp;row2) == 5) ...data is OK... </code></pre> <p>Since you're using an offset and were capturing where the scan ended, you would use:</p> <pre><code>while (sscanf(matrix[i][c] + offset, " %c%d %c %c%d%n", &amp;col1, &amp;row1, &amp;op, &amp;col2, &amp;row2, &amp;readCharCount) == 5) ...data is OK... </code></pre> <p>Note that the <code>%n</code> conversion specifier is not counted, so the test remains against 5, not 6.</p> <p>Also note the careful placement of spaces in the format string. They're necessary and flexible (that would handle <code>A1+B2</code> OK, as well as <code>A1 + B2</code>). If you are going to allow bigger spreadsheets, you might prefer to specify:</p> <pre><code>while (sscanf(matrix[i][c] + offset, " %4[a-zA-Z]%d %c %4[a-zA-Z]%d%n", col1, &amp;row1, &amp;op, col2, &amp;row2, &amp;readCharCount) == 5) ...data is OK... </code></pre> <p>where the type of <code>col1</code> and <code>col2</code> changes from a single to <code>char col1[5]; char col2[5];</code> (which is why the <code>&amp;</code> was dropped, too). The scan sets allow inputs like <code>aAa1 + BbB2</code> to be recognized. Because of the <code>%d</code> notation, spaces are allowed between the letter or letters and the number (so the code would allow <code>aaa 999 + bbb 888</code>. Avoiding that is hard; I think you'd need to process the data with two scansets:</p> <pre><code>while (sscanf(matrix[i][c] + offset, " %4[a-zA-Z]%5[0-9] %c %4[a-zA-Z]%5[0-9]%n", col1, row1, &amp;op, col2, row2, &amp;readCharCount) == 5) ...data is OK... </code></pre> <p>where the types are now <code>char row1[6]; char row2[6];</code> and the ampersands have been dropped again. You can then confidently convert <code>row1</code> and <code>row2</code> into numbers.</p> <p>See also: <a href="https://stackoverflow.com/questions/7651397/calc-cell-convertor-in-c">Calc cell convertor in C</a> for code to convert column numbers into the corresponding alphabetic codes.</p>
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    1. USJonathan Leffler
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    1. COi tried the last example and it became a infinity loop. i will have more than 2 "pairs" of row and col, can i put this to became automatically? while (sscanf(matris[i][c] + offset, " %4[a-zA-Z]%5[0-9] %c %4[a-zA-Z]%5[0-9]%n", col1, row1, &op, col2, row2, &readCharCount) == 5){ printf("Col: %s, LIne: %s, OP: %c\n", col1, row1, op); printf("Col: %s, LIne: %s, OP: %c\n", col2, row2, op); } thanks
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    2. COYou would have to add `readCharCount` to `offset` to resume reading where the first call left off; that would be in the `...data is OK...` loop body. Otherwise, you keep reading the same part of the string over and over again, which is indeed an infinite loop.
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    3. COi tryied http://pastebin.com/LM8326Gz and input A1+C2+D3+B3 and my result was: A1, C2, + => ONLY. what i did wrong?
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