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Task/Reduced-row-echelon-form/Swift/reduced-row-echelon-form.swift

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+var lead = 0
+var rowCount = eCount
+var columnCount = mCount
+for (var r = 0; r < rowCount; ++r) {
+	if (columnCount <= lead) {
+     		break
+    	}
+	var i = r
+	while (matrix[i][lead] == 0) {
+    		++i
+   		if (i == rowCount) {
+  			i = r
+  			++lead
+ 			if (columnCount == lead) {
+				--lead
+				break
+  			}
+    		}
+	}
+	for (var j = 0; j < columnCount; ++j) {
+   		var temp = matrix[r][j]
+    		matrix[r][j] = matrix[i][j]
+   		matrix[i][j] = temp
+	}
+	var div = matrix[r][lead]
+	if (div != 0) {
+    		for (var j = 0; j < columnCount; ++j) {
+  			matrix[r][j] /= div
+    		}
+	}
+	for (var j = 0; j < rowCount; ++j) {
+    		if (j != r) {
+  			var sub = matrix[j][lead]
+  			for (var k = 0; k < columnCount; ++k) {
+				matrix[j][k] -= (sub * matrix[r][k])
+  			}
+    		}
+	}
+	++lead
+}